Mediated electrochemical oxidation used for the destruction of organics contaminated with radioactive materials, dissoulution of atransuranics, and the decontamination of equipment contaminated with mixed waste

ABSTRACT

A mixed waste mediated electrochemical oxidation process (MEO) process and apparatus for the dissolution of transuranic elements, and/or compounds thereof in transuranic waste, low level waste (LLW), low level mixed waste, special case waste, and greater than class C LLWS, and also the destruction of the non-fluorocarbon organic component in the waste. The MEO process and apparatus operates in three different modes: dissolution, destruction, and decontamination. In the first mode, dissolution, the process runs until the transuranics such as a mixed oxide or carbide, and/or mixture of oxides or carbides of uranium and plutonium are totally dissolved into solution. The second mode, destruction, the process is operated such that the mixed waste materials are reduced to CO 2 , water and small amounts of inorganic salts. The third mode, decontamination, involves contaminated equipment. In the decontamination mode the MEO process destroys the mixed wastes that have contaminated the equipment.

This application claims the benefit of U.S. Provisional Application No.60/398,808, filed Jul. 29, 2002.

FIELD OF THE INVENTION

This invention relates generally to the use of a MediatedElectrochemical Oxidation process and apparatus for: (a)the dissolutionof transuranic elements (e.g., plutonium, neptunium, americium, curium,and californium), and/or compounds thereof in transuranic waste (TRUW),low level waste (LLW), low level mixed waste (LLMW), special case waste(SCW), and greater than class C (GTCC) LLW's;. (b) the destruction ofthe non-fluorocarbon organic component in these waste types; and (c) thedecontamination of transuranic/actinide contaminated equipment.

These various waste forms are defined as follows:

Transuranic Waste—TRUW is waste containing more than 100 nanocuries pergram of alpha-emitting transuranic isotopes, with half lives greaterthan 20 years, except for (a) high-level waste (HLW), (b) waste that theDepartment of Energy (DOE) has determined, with the concurrence of theU.S. Environmental Protection Agency (EPA), does not need the degree ofisolation required by 40CFR 191, or (c) waste the U.S. NuclearRegulatory Commission (NRC) has approved for disposal on a case by casebasis in accordance with 10CFR 61. TRUW has radioactive components suchas plutonium, with lesser amounts of neptunium, americium, curium, andcalifornium, and/or compounds thereof, and may also contain hazardouswaste (HW) components subject to the Resource Conservation and RecoveryAct (RCRA) (42USC 6901 et seq.).

High Level Waste—HLW is the highly radioactive waste material thatresults form the reprocessing of spent nuclear fuel, including liquidwaste produced directly from reprocessing and any solid waste derivedfrom the liquid that contains a combination of transuranic and fissionproduct nuclides in quantities that require permanent isolation. Highlevel waste may include other highly radioactive material that the NRC,consistent with existing law, determines by rule requires permanentisolation.

Hazardous Waste—HW is defined under the RCRA (42USC 6901 et seq.) as asolid waste, or combination of solid wastes, which because of itsquantity, concentration, or physical, chemical, or infectiouscharacteristics may (a) causes or significantly contribute to anincrease in mortality or an increase in serious irreversible, orincapacitating reversible, illness or (b) pose a substantial present orpotential hazard to human health or the environment when improperlytreated, stored, transported, disposed or, or otherwise managed. RCRAdefines a “solid” waste to include solid, liquid, semisolid, orcontained gaseous materials. By definition HW alone contains noradioactive components.

Low Level Waste—LLW includes all radioactive waste that is notclassified as HLW, TRUW, spent nuclear fuel, or byproduct tailingscontaining uranium or thorium from processed ore (as defined in Section11(e)(2) of the Atomic Energy Act (AEA) of 1954 [42USC 2011 et seq.]).Test specimens of fissionable materials irradiated for research anddevelopment only, and not for the production of power or plutonium maybe classified as LLW provided the concentration of transuranics is lessthan 100 nanocuries per gram of waste. Most LLW consists of relativelylarge amounts of non-RCRA controlled waste materials contaminated withsmall amounts of radio nuclides, such as contaminated equipment (e.g.,glove boxes, ventilation ducts, shielding, and laboratory apparatus,etc.), protective clothing, paper, rags, packing material, ion exchangeresins, and solidified sledges.

Low Level Mixed Waste—LLMW contains both hazardous waste (HW) componentssubject RCRA (42USC 6091 et seq.) and low-level radioactive waste (LLW)components subject to the AEA of 54 (42USC 2011, et seq.).

Special Case Waste—SCW is radioactive waste owned or generated by DOEthat does not fit into typical management plans developed for the majorradioactive waste types (e.g., HLW, LLW, LLMW, TRUW, etc.). For example,LLW that because of its high radioactivity levels cannot currently bedisposed of at existing DOE LLW disposal facilities without exceedingtheir performance standards and TRUW that cannot meet geologicaldisposal acceptance criteria are SCW.

Greater Than Class C LLW—GTCC LLW is waste that exceeds the NuclearRegulatory Commission (NRC) radioisotope concentration limits for ClassC LLW as specified in 10CFR 61, and thus exceeds the limits for shallowland burial. Commercial GTCC LLW includes, but is not limited to,activated metals, process wastes, other contaminated solids generatedfrom the operation of commercial nuclear power plants, and radioactivematerials that are used in mineral exploration and as part of medicaltreatments.

Henceforth all the aforementioned waste forms, except HLW and HW, shallbe collectively referred to as “mixed waste”.

The following documents are added to the definition sp as to furtherclarify the scope and definition or mixed waste as any waste that isconsidered by any of, but not limited to, the following statutes andregulation:

-   -   10 CFR 20 Chapter I Nuclear Regulatory Commission, Subpart K,        20.2005 Disposal of Specific Waste    -   10 CFR 20 Chapter I Nuclear Regulatory Commission, Part 20        Standard for Protection Against Radiation, Subpart A-general        Provisions, Sec 20.1003 definitions    -   10 CFR 20 Chapter I Nuclear Regulatory Commission, Licensing        requirements for Land Disposal of Radioactive Waste, Sec 61.55        Waste Classification    -   32 CFR 627 Bio Defense Safety Program technical Safety        Regulations, Sec 627.34 Disposal

In addition to the aforementioned treatment of mixed waste, thisinvention relates to a process and apparatus for the dissolution oftransuranic elements in mixed oxides, carbides, and nitrides formed bytheir co-precipitation, mechanical mixing, etc. with similar uraniumcompounds.

The MEO process and apparatus operates in three different modes;dissolution, destruction, and decontamination. When non-radioactivematerials are combined in the same waste they are henceforth referred toas mixed waste. The principle component of mixed waste of concern inthis patent is the organic materials that are contaminated withradioactive compounds. In the first mode (dissolution) the process runsuntil the transuranics (such as a mixed oxide or carbide, and/or mixtureof oxides or carbides of uranium and plutonium) are totally dissolvedinto solution. The second mode (destruction) the process is operatedsuch that the mixed waste materials are reduced to a CO₂, water andsmall amounts of inorganic salts.

The third mode (decontamination) involves contaminated equipment,instruments, glassware, containers (e.g., 50 gallon drums, etc.) andmaterials. In this mode the MEO process destroys the mixed wastes thathave contaminated them and places the transuranic/transuranic/actinidesinto solution.

The basis of the process is a mediated electrochemical oxidation processin which one or more regenerable oxidizing redox couples (specified inTables I and II) interact with the mixed waste to decompose it. Theoxidizers are present in electrolytic solutions that are acidic,alkaline, or neutral, operating in the temperature range of just abovethe freezing point and just below the boiling point temperatures of theelectrolyte and at ambient atmosphere pressure. The process is animprovement over the state of the art relative to oxidizers andelectrolytes represented in existing patented processes and apparatus.

BACKGROUND OF THE INVENTION

Mixed waste is a growing problem for today's technological society. Themixed waste generated by our Federal government and local electricalutilities sector is an increasing burden on these activities as well asa concern for the whole country in general.

The cost of disposing of mixed waste or transuranic/actinides in theU.S. are a multi-billion dollar per year program. The Department ofEnergy report Current and Planned Low-Level Waste Disposal CapacityReport Revision 1, Sep. 18, 1998 estimates the volume of low-level andmixed waste to be approximately 8.1 billion cubic feet during the period1998 to 2070. All companies and institutions and businesses thatgenerate and handle this category of waste or transuranic/actinides mustprovide safe, effective and preferably, inexpensive disposal of thewaste or transuranic/actinides. In recent years there has beenincreasing concern over the disposal of mixed waste and/ortransuranic/actinides. The principle method for the handling of thismixed waste and/or transuranic/actinides are self-storage ortransportation to other facilities. The NRC and DOE have issued newregulations that require very stringent levels of control andmaintenance of the storage facilities. The new regulations will, forpractical purposes, require major modifications to almost all suchstorage facilities in the foreseeable future. Storage and transportationfacilities have already begun to limit acceptance of mixed waste and/ortransuranic/actinides, especially if it is from other then their ownexisting relationships Processes based on the use of silver, cobalt,cerium and peroxysulfate have been proposed, but each has severelimitations.

Research into the application of the MEO process to date has involvedthe use of the process to dispose of materials in several areas. In thefirst area, the MEO process uses an electrochemical cell in which theelectrolyte is restricted to a composition of nitric acid and silverions in a specific temperature, concentration, and pH range. The silverions serve as the regenerable mediating oxidizing species which is usedin an oxidative dissolution process to recover plutonium contained insolid waste from processes, technological and laboratory waste (U.S.Pat. No. 4,749,519), and subsequently extended to the dissolution of theplutonium dioxide component of uranium and plutonium oxide mixtures(i.e. mixed oxide reactor fuel) (U.S. Pat. No. 5,745,835).

In the second area, the MEO process was used for the oxidation (i.e.,decomposition) of organic matter contaminated with radioactivematerials, such as that contained in the solid waste generated inextracting plutonium from irradiated nuclear reactor fuel ( U.S. Pat.Nos. 4,874,485; 4,925,643.

Both of the two areas discussed have involved similar use of the MEOprocess using nitric acid and silver ions being generated by anelectrochemical cell with the anode and cathode being separated by amembrane. The two uses have differed in the temperature range used ineach of the applications. The first use is operated below 50° C. (i.e.,generally around 25° C. or room temperature) to minimize water reactionswith the Ag(II) ion, which are parasitic as they do not assist indissolution of the plutonium dioxide, but do consume electrons, thusreducing the coulombic efficiency of the process. The second use isoperated between 50° C. and slightly below 100° C. to promote reactionof the Ag(II) ions with the nitric acid solution which produces a rangeof highly reactive free radicals (e.g., .OH, .O₂H, .NO₃, etc) and H₂O₂,all of capable oxidizing organic materials.

Others have substituted cerium and nitric acid; and cobalt, and nitricacid, sulfuric acid or neutral solutions for the silver and nitric acidas the electrolyte (U.S. Pat. Nos. 4,686,019, 5,516,972, 5,756,874,5,911,868, and 5,919,350). The temperatures vary among the electrolytesbeing substituted for the silver and nitric acid combination. Followingthe aforementioned work a U.S. Pat. No. 5,952,542, ruthenium (alsomentioned are osmium, iridium, and rhodium) has been proposed as theelectrolyte for the MEO process, to decompose organic materials in aslightly acidic solution operating between 60° C. and 90° C.

Most recently in U.S. Pat. No. 6,096,283, peroxydisulfate is used in asystem combining hydrolysis and direct chemical oxidation (DCO). Thehydrolysis is performed under the following conditions: at 100° C. to120° C., a pH of greater then 7 and at greater than atmosphericpressure. The DCO is operated at temperatures at or less then 105° C.,atmospheric pressure, and under alkaline, neutral and acidic conditions.The stated purpose of this patent is to destroy halogenated organicsolvents, contaminated soils and sludge, and organic components of mixedwaste.

All of the descriptions reviewed are similar in their application to thedecomposition of organic materials and each patent has restricted theanions, cations, electrolyte, pH and temperature range used.

The processes defined in the foregoing patents each have severelimitations in their techniques and apparatus for using silver, cobalt,cerium and peroxysulfate. The silver based process requires the presenceof strong nitric acid for the formation of a useful population of theAg⁺² oxidizing species and silver is removed from the system byparasitic reactions if halogens are present in the mixed waste. Silverions diffusion across the membrane from the anolyte to the catholytewhere it is necessary to conduct a recovery process due to the high costof silver. Reduction of the concentrated nitric acid at the cathodeultimately leads to the formation of NO_(x) in the cathode chamber, thusnecessitating inclusion of a cathode off-gas treatment system.

The lower oxidation potential of cobalt and cerium species relative tomany oxidizing species listed in Tables 1 and 2 herein, limit theirability to decompose some of the components of mixed waste and/ortransuranic/actinides, at a practical rate. Both cobalt and cerium arecostly for an industrial process and their migration through themembrane will require a recovery system.

This patent offer new features for an MEO process and apparatus notcover in the present art which address these limitations the features inthis patent are: (a) alternative redox couple species, (b) differentanolyte and catholyte electrolytes in the same MEO process andapparatus, (c) MEO apparatus design provides for the same apparatususing many different redox couples without changing the apparatus, (d)MEO process avoids the emission of NO_(x), (e) redox couples andelectrolyte(s) can directly replace silver II in the existing apparatusto eliminate their major problems, (f) the redox couples dissolveplutonium oxides, nitrides or carbides, uranium oxides, nitrides orcarbides, and other transuranics/actinides directly in to solution forease of recovery.

These and further and other objects and features of the invention areapparent in the disclosure, which includes the above and ongoing writtenspecification, with the drawings.

SUMMARY OF THE INVENTION

This invention relates generally to the use of a MediatedElectrochemical Oxidation process and apparatus for: the dissolution oftransuranic/actinide elements (e.g., plutonium, neptunium, americium,curium, and californium), and/or compounds thereof in transuranic waste(TRUW), low level waste (LLW), low level mixed waste (LLMW), specialcase waste (SCW), and greater than class C (GTCC) LLW's;. thedestruction of the non-fluorocarbon organic component in these wastetypes; and the decontamination of transuranic/actinide contaminatedequipment.

Using this MEO methodology and process nearly all solid or liquid mixedwastes are decomposed into carbon dioxide, water, and trace amounts ofinorganic salts. The tranuranics/actinides are placed into solutionduring the decomposition of the mixed waste. The process may be operatedin three different modes (dissolution, destruction, anddecontamination).

In the first mode (dissolution) the process runs until the mixed wastetransuranic elements in mixed oxides, carbides, and nitrides formed bytheir co-precipitation, mechanical mixing, etc. with similar uraniumcompounds materials are totally decomposed dissolved into solution thesebenign natural components as previously mentioned.

The second mode (destruction) the process involves mixed wastematerials. In this mode the MEO process destroys the mixed wastematerials by reducing them to C_(2,) water and small amounts ofinorganic salts. The transuranic material on the mixed waste isdissolved into solution and separated from the MEO electrolyte.

The third mode (decontamination) involves contaminated equipment,instruments, glassware, containers (e.g., metal or plastic drums, etc.)and materials (e.g., clothing, rags, absorbents, etc.). In this mode theMEO process dissolves the radioactive component of the mixed waste anddestroys the organic component. These items are placed in an anolytereaction chamber(s) (see FIGS. 1B, 1C, 1D, and 1E) and the electrolytecontaining the oxidizing species is introduced into the chamber(s). TheMEO process cleans the contaminated items rendering them non-toxic andsafe for reuse or disposal and places the radioactive materials intosolution for capture and removal.

The MEO process involves the anolyte portion of the electrolytecontaining one or more redox couples, wherein the oxidized form of atleast one redox couple is produced by anodic oxidation at the anode ofan electrochemical cell. The oxidized forms of any other redox couplespresent are produced either by similar anodic oxidation or reaction withthe oxidized form of other redox couples present capable of affectingthe required redox reaction. The anodic oxidation in the electrochemicalcell is driven by an externally induced electrical potential inducedbetween the anode(s) and cathode(s) of the cell. The oxidized species ofthe redox couples oxidize the mixed waste molecules and are themselvesconverted to their reduced form, whereupon they are reoxidized by eitherof the aforementioned mechanisms and the redox cycle continues until alloxidizable waste species, including intermediate reaction products, haveundergone the desired degree of oxidation. The redox species ions arethus seen to “mediate” the transfer of electrons from the wastemolecules to the anode, (i.e., oxidation of the waste).

A membrane in the electrochemical cell separates the anolyte andcatholyte, thereby preventing parasitic reduction of the oxidizingspecies at the cathode. The membrane is ion-selective or semi-permeable(i.e., microporous plastic, porous ceramic, sintered glass frit, etc.).The preferred MEO process uses the mediator species described in Table I(simple anions redox couple mediators); the Type I isopolyanions (IPA)formed by Mo, W, V, Nb, and Ta, and mixtures thereof; the Type Iheteropolyanions (HPA) formed by incorporation into the aforementionedisopolyanions of any of the elements listed in Table II (heteroatoms)either singly or in combinations there of; any type heteropolyanioncontaining at least one heteropolyatom (i.e. element) contained in bothTable I and Table II; or combinations of mediator species from any orall of these generic groups.

Simple Anion Redox Couple Mediators

Table I show the simple anion redox couple mediators used in thepreferred MEO process wherein “species” defines the specific ions foreach chemical element that have applicability to the MEO process aseither the reduced (e.g., Fe⁺³) or oxidizer (e.g., FeO₄ ⁻²) form of themediator characteristic element (e.g., Fe), and the “specific redoxcouple” defines the specific associations of the reduced and oxidizedforms of these species (e.g., Fe⁺³/FeO₄ ⁻²) that are claimed for the MEOprocess. Species soluble in the anolyte are shown in Table I in normalprint while those that are insoluble are shown in bold underlined print.The characteristics of the MEO Process claimed in this patent arespecified in the following paragraphs.

The anolyte contains one or more redox couples which in their oxidizedform consist of either single multivalent element anions (e.g., Ag⁺²,Ce⁺⁴, Co⁺³, Pb⁺⁴, etc.), insoluble oxides of multivalent elements (e.g.,PbO₂, CeO₂, PrO₂, etc.), or simple oxoanions (also called oxyanions) ofmultivalent elements (e.g., FeO₄ ⁻², NiO₄ ⁻², BiO₃ ⁻, etc.). The redoxcouples in their oxidized form are called the mediator species. Thenonoxygen multivalent element component of the mediator is called thecharacteristic element of the mediator species. We have chosen to groupthe simple oxoanions with the simple anion redox couple mediators ratherthan with the complex (i.e., polyoxometallate (POM)) anion redox couplemediators discussed in the next section and refer to them collectivelyas simple anion redox couple mediators.

In one embodiment of this process both the oxidized and reduced forms ofthe redox couple are soluble in the anolyte. The reduced form of thecouple is anodically oxidized to the oxidized form at the cell anode(s)whereupon it oxidizes molecules of mixed wastes either dissolved in orlocated on waste particle surfaces wetted by the anolyte, with theconcomitant reduction of the oxidizing agent to its reduced form,whereupon the MEO process begins again with the reoxidation of thisspecies at the cell anode(s). If other less powerful redox couples ofthis type (i.e., reduced and oxidized forms soluble in anolyte) arepresent, they too may undergo direct anodic oxidation or the anodicallyoxidized more powerful oxidizing agent may oxidize them rather than awaste molecule. The weaker redox couple(s) is selected such that theiroxidation potential is sufficient to affect the desired reaction withthe waste molecules. The oxidized species of all the redox couplesoxidize the mixed waste molecules and are themselves converted to theirreduced form, whereupon they are reoxidized by either of theaforementioned mechanisms and the redox cycle continues until alloxidizable waste species, including intermediate reaction products, haveundergone the desired degree of oxidation.

The preferred mode for the MEO process as described in the precedingsection is for the redox couple species to be soluble in the anolyte inboth the oxidized and reduced forms, however this is not the only modeof operation claimed herein. If the reduced form of the redox couple issoluble in the anolyte (e.g., Pb⁺²) but the oxidized form is not (e.g.,PbO₂), the following processes are operative. The insoluble oxidizingagent is produced either as a surface layer on the anode by anodicoxidation, or throughout the bulk of the anolyte by reacting with theoxidized form of other redox couples present capable of affecting therequired redox reaction, at least one of which is formed by anodicoxidation. The oxidizable waste is either soluble in the anolyte ordispersed therein at a fine particle size, (e.g., emulsion, colloid,etc.) thereby affecting intimate contact with the surface of theinsoluble oxidizing agent (e.g., PbO₂) particles. Upon reaction of thewaste with the oxidizing agent particles, the waste is oxidized and theinsoluble oxidizing agent molecules on the anolyte wetted surfaces ofthe oxidizing agent particles reacting with the waste are reduced totheir soluble form and are returned to the bulk anolyte, available forcontinuing the MEO process by being reoxidized.

In another variant of the MEO process, if the reduced form of the redoxcouple is insoluble in the anolyte (e.g., TiO₂) but the oxidized form issoluble (e.g., TiO₂ ⁺²), the following processes are operative. Thesoluble (i.e., oxidized) form of the redox couple is produced by thereaction of the insoluble (i.e., reduced form) redox couple molecules onthe anolyte wetted surfaces of the oxidizing agent particles with thesoluble oxidized form of other redox couples present capable ofaffecting the required redox reaction, at least one of which is formedby anodic oxidation and soluble in the anolyte in both the reduced andoxidized forms. The soluble oxidized species so formed are released intothe anolyte whereupon they oxidize waste molecules in the mannerpreviously described and are themselves converted to the insoluble formof the redox couple, thereupon returning to the starting point of theredox MEO cycle.

In this invention, when an alkaline anolyte is used, the CO₂ resultingfrom oxidation of the mixed waste reacts with the anolyte to form alkalimetal bicarbonates/carbonates. The bicarbonate/carbonate ions circulatewithin the anolyte where they are reversibly oxidized to percarbonateions either by anodic oxidation within the electrochemical cell oralternately by reacting with the oxidized form of a more powerful redoxcouple mediator, when present in the anolyte. The carbonate thusfunctions exactly as a simple anion redox couple mediator, therebyproducing an oxidizing species from the waste oxidation products that itis capable of destroying additional mixed waste.

The electrolytes used in this patent are from a family of acids, alkali,and neutral salt aqueous solutions (e.g. sulfuric acid, potassiumhydroxide, sodium sulfate aqueous solutions, etc.).

A given redox couple or mixture of redox couples (i.e. mediator species)are to be used with different electrolytes.

The electrolyte composition is selected based on demonstrated adequatesolubility of the compound containing at least one of the mediatorspecies present in the reduced form (e.g., sulfuric acid may be usedwith ferric sulfate, etc.).

The concentration of the mediator species containing compounds in theanolyte may range from 0.0005 molar (M) up to the saturation point.

The concentration of electrolyte in the anolyte is governed by itseffect upon the solubility of the mediator species containing compoundsand by the conductivity of the anolyte solution desired in theelectrochemical cell for the given mediator species being used.

The temperature over which the electrochemical cell may be operatedranges from approximately 0° C. to slightly below the boiling point ofthe electrolytic solution. By using simple and/or complex redox couplesmediators and attacking specific organic molecules with the oxidizingspecies while operating at low temperature, the formation of toxicmaterials such as dioxin and furans is prevented.

The MEO process is operated at ambient atmospheric pressure.

The mediator species are differentiated on the basis of whether they arecapable of reacting with the electrolyte to produce free radicals (e.g.,.O₂H (perhydroxyl), .OH (hydroxyl), .SO₄ (sulfate), .NO₃ (nitrate),etc.). Such mediator species are classified herein as “super oxidizers”(SO) and typically exhibit oxidation potentials at least equal to thatof the Ce⁺³/Ce⁺⁴ redox couple (i.e., 1.7 volts at 1 molar, 25° C. and pH1).

The electrical potential between the electrodes in the electrochemicalcell is based upon the oxidation potential of the most reactive redoxcouple presents in the anolyte and serving as a mediator species, andthe ohmic losses within the cell. In the case of certain electrolytecompositions a low level AC voltage is impressed upon the DC voltage toretard the formation of cell performance limiting surface films on theelectrode and/or membranes. Within the current density range of interestthe electrical potential may be approximately 2.5 to 3.0 volts.

Complex Anion Redox Couple Mediators

The preferred characteristic of the oxidizing species in the MEO processis that it be soluble in the aqueous anolyte in both the oxidized andreduced states. The majorities of metal oxides and oxoanion (oxyanion)salts are insoluble, or have poorly defined or limited solutionchemistry. The early transition elements, however, are capable ofspontaneously forming a class of discrete polymeric structures calledpolyoxometallate (POMs) which are highly soluble in aqueous solutionsover a wide pH range. The polymerization of simple tetrahedral oxoanionsof interest herein involves an expansion of the metal, M, coordinationnumber to 6, and the edge and corner linkage of MO₆ octahedra. Chromiumis limited to a coordination number of 4, restricting the POMs based onCrO₄ tetrahedra to the dichromate ion [Cr₂O₇]⁻² which is included inTable I. Based upon their chemical composition POMs are divided into thetwo subclasses isopolyanions (IPAs) and heteropolyanions (HPAs), asshown by the following general formulas:Isopolyanions (IPAs)−[M_(m)O_(y)]^(p−)and,Heteropolyanions (HPAs)−[X_(x)M_(m)O_(y)]^(q−)(m>x)

where the addenda atom, M, is usually Molybdenum (Mo) or Tungsten (W),and less frequently Vanadium (V), Niobium (Nb), or Tantalum (Ta), ormixtures of these elements in their highest (d⁰) oxidation state. Theelements that can function as addenda atoms in IPAs and HPAs appear tobe limited to those with both a favorable combination of ionic radiusand charge, and the ability to form dn-pn M-O bonds. However, theheteroatom, X, have no such limitations and can be any of the elementslisted in Table II.

There is a vast chemistry of POMs that involves the oxidation/reductionof the addenda atoms and those heteroatoms listed in Table II thatexhibit multiple oxidation states. The partial reduction of the addenda,M, atoms in some POMs strictures (i.e., both IPAs and HPAs) producesintensely colored species, generically referred to as “heteropolyblues”. Based on structural differences, POMs can be divided into twogroups, Type I and Type II. Type I POMs consist of MO₆ octahedra eachhaving one terminal oxo oxygen atom while Type II have 2 terminal oxooxygen atoms. Type II POMs can only accommodate addenda atoms with d⁰electronic configurations, whereas Type I; e.g., Keggin (XM₁₂O₄₀),Dawson (X₂M₁₈O₆₂), hexametalate (M₆O₁₉), decatungstate (W₁₀O₃₂), etc.,can accommodate addenda atoms with d⁰, d¹, and d² electronicconfigurations. Therefore, while Type I structures can easily undergoreversible redox reactions, structural limitations preclude this abilityin Type II structures. Oxidizing species applicable for the MEO processare therefore Type I POMs (i.e., IPAs and HPAs) where the addenda, M,atoms are W, Mo, V, Nb, Ta, or combinations there of.

The high negative charges of polyanions often stabilize heteroatoms inunusually high oxidation states, thereby creating a second category ofMEO oxidizers in addition to the aforementioned Type I POMs. Any Type Ior Type II HPA containing any of the heteroatom elements, X, listed inTable II, that also are listed in Table I as simple anion redox couplemediators, can also function as an oxidizing species in the MEO process.

The anolyte contains one or more complex anion redox couples, eachconsisting of either the afore mentioned Type I POMs containing W, Mo,V, Nb, Ta or combinations there of as the addenda atoms, or HPAs havingas heteroatoms (X) any elements contained in both Tables I and II, andwhich are soluble in the electrolyte (e.g. sulfuric acid, etc.).

The electrolytes used in this claim are from a family of acids, alkali,and neutral salt aqueous solutions (e.g. sulfuric acid, potassiumhydroxide, sodium sulfate aqueous solutions, etc.).

A given POM redox couple or mixture of POM redox couples (i.e., mediatorspecies) may be used with different electrolytes.

The electrolyte composition is selected based on demonstrating adequatesolubility of at least one of the compounds containing the POM mediatorspecies in the reduced form and being part of a redox couple ofsufficient oxidation potential to affect oxidation of the other mediatorspecies present.

The concentration of the POM mediator species containing compounds inthe anolyte may range from 0.0005M (molar) up to the saturation point.

The concentration of electrolyte in the anolyte may be governed by itseffect upon the solubility of the POM mediator species containingcompounds and by the conductivity of the anolyte solution desired in theelectrochemical cell for the given POM mediator species being used toallow the desired cell current at the desired cell voltage.

The temperature over which the electrochemical cell may be operatedranges from approximately 0° C. to just below the boiling point of theelectrolytic solution. If the temperature range for any given processreaches the 200° C. to 300° C., then they have the potential to producevolatile organics that may have serious health and environmentalconsequences. Typical of these substances are dioxins and furans, whichare, controlled materials.

The MEO process is operated at ambient atmospheric pressure.

The POM mediator species are differentiated on the basis of whether theyare capable of reacting with the electrolyte to produce free radicals(e.g., .O₂H, .OH, .SO₄, .NO₃). Such mediator species are classifiedherein as “super oxidizers” (SO) and typically exhibit oxidationpotentials at least equal to that of the Ce⁺³/Ce⁺⁴ redox couple (i.e.,1.7 volts at 1 molar, 25° C. and pH 1).

The electrical potential between the anode(s) and cathode(s) in theelectrochemical cell is based on the oxidation potential of the mostreactive POM redox couple presents in the anolyte and serving as amediator species, and the ohmic losses within the cell. Within thecurrent density range of interest the electrical potential may beapproximately 2.5 to 3.0 volts. AC voltage

In the case of certain electrolyte compositions, a low level isimpressed across the electrodes in the electrochemical cell. The ACvoltage is used to retard the formation of surface films on theelectrodes and/or membranes that would have a performance limitingeffect.

Mixed Simple and Complex Anion Redox Couple Mediators

The preferred MEO process for a combination of simple anion redox couplemediators (A) and complex anion redox couple mediators (B) may be mixedtogether to form the system anolyte. The characteristics of theresulting MEO process is similar to the previous discussions.

The use of multiple oxidizer species in the MEO process has thefollowing potential advantages-:

-   -   a. The overall mixed waste destruction rate is increased if the        reaction kinetics of anodically oxidizing mediator “A”,        oxidizing mediator “B” and oxidized mediator “B” oxidizing the        mixed waste and/or transuranic/actinides is sufficiently rapid        such that the combined speed of the three step reaction train is        faster than the two step reaction trains of anodically oxidizing        mediator “A” or “B”, and the oxidized mediators “A” or “B”        oxidizing the organic waste and/or transuranic/actinides.    -   b. If the cost of mediator “B” is sufficiently less than that of        mediator “A”, the used of the above three step reaction train        results in lowering the cost of mixed waste and/or        transuranic/actinides destruction due to the reduced cost        associated with the smaller required inventory and process        losses of the more expensive mediator “A”. An example of this is        the use of silver (II)-peroxysulfate mediator system to reduce        the cost associated with a silver (I/II) only MEO process and        overcome the slow anodic oxidation kinetics of a        sulfate/peroxysulfate only MEO process.    -   c. The MEO process is “desensitized” to changes in the types of        molecular bonds present in the mixed waste as the use of        multiple mediators, each selectively attacking different types        of chemical bonds, results in a highly “nonselective” oxidizing        system.

Anolyte Additional Features

In one preferred embodiment of the MEO process in this invention, thereare one or more simple anion redox couple mediators in the anolyteaqueous solution. In a preferred embodiment of the MEO process, thereare one or more complex anion (i.e., POMs) redox couple mediators in theanolyte aqueous solution. In another preferred embodiment of the MEOprocess, there are one or more simple anion redox couples and one ormore complex anion redox couples in the anolyte aqueous solution.

The MEO process of the present invention uses any oxidizer specieslisted in Table I that are found in situ in the mixed waste to bedestroyed; For example, when the mixed waste also contains leadcompounds that become a source of Pb⁺² ions under the MEO processconditions within the anolyte, the waste-anolyte mixture may becirculated through an electrochemical cell. Where the oxidized form ofthe reversible lead redox couple may be formed either by anodicoxidation within the electrochemical cell or alternately by reactingwith the oxidized form of a more powerful redox couple, if present inthe anolyte and the latter being anodically oxidized in theelectrochemical cell. The lead thus functions exactly as a simple anionredox couple species thereby destroying the mixed waste organiccomponent leaving only the lead and the transuranic/actinides to bedisposed of. Adding one or more of any of the anion redox couplemediators described in this patent further enhances the MEO processdescribed above.

In the MEO process of the invention, anion redox couple mediators in theanolyte part of an aqueous electrolyte solution uses an acid, neutral oralkaline solution depending on the temperature and solubility of thespecific mediator(s). In the presence of halogenated hydrocarbons in themixed waste additional processes are ongoing. The anion oxidizers usedin the basic MEO process preferably attack specific halogenatedhydrocarbon molecules. Hydroxyl free radicals preferentially attackhalogenated hydrocarbon molecules containing aromatic rings andunsaturated carbon-carbon bonds. Oxidation products such as the highlyundesirable aromatic compounds chlorophenol or tetrachlorodibenzodioxin(dioxin) upon formation would thus be preferentially attacked byhydroxyl free radicals, preventing the accumulation of any meaningfulamounts of these compounds. Even free radicals with lower oxidationpotentials than the hydroxyl free radical preferentially attackcarbon-halogen bonds such as those in carbon tetrachloride andpolychlorobiphenyls (PCBs).

Some redox couples having an oxidation potential at least equal to thatof the Ce⁺³/Ce⁺⁴ redox couple (i.e., 1.7 volts at 1 molar, 25° C. and pH1), and sometimes requiring heating to above about 50° C. (i.e., butless then the boiling point of the electrolyte) can initiate a secondoxidation process wherein the mediator ions in their oxidized forminteract with the aqueous anolyte, creating secondary oxidizer freeradicals (e.g., .O₂H, .OH, .SO₄, .NO₃, etc.) or hydrogen peroxide. Suchmediator species in this invention are classified herein as “superoxidizers” (SO) to distinguish them from the “basic oxidizers” incapableof initiating this second oxidation process.

The oxidizer species addressed in this patent (i.e., characteristicelements having atomic number below 90) are described in Table I (simpleanions redox couple mediators): Type I IPAs formed by Mo, W, V, Nb, Ta,or mixtures there of as addenda atoms; Type I HPAs formed byincorporation into the aforementioned IPAs if any of the elements listedin Table II (heteroatoms) either singly or in combinations thereof; orany HPA containing at least one heteroatom type (i.e., element)contained in both Table I and Table II; or mediator species from any orall of these generic groups.

Each oxidizer anion element has normal valence states (NVS) (i.e.,reduced form of redox couple) and higher valence states (HVS) (i.e.,oxidized form of redox couple) created by stripping electrons off NVSspecies when they pass through and electrochemical cell. The MEO processof the present invention uses a broad spectrum of anion oxidizers; theseanion oxidizers used in the basic MEO process may be interchanged in thepreferred embodiment without changing the equipment.

In preferred embodiments of the MEO process, the basic MEO process ismodified by the introduction of additives such as tellurate or periodateions which serve to overcome the short lifetime of the oxidized form ofsome redox couples (e.g., Cu⁺³) in the anolyte via the formation of morestable complexes (e.g., [Cu (IO₆)₂]⁻⁷, [Cu(HTeO₆)₂]⁻⁷). The tellurateand periodate ions can also participate directly in the MEO process asthey are the oxidized forms of simple anion redox couple mediators (seeTable I) and participate in the oxidation of mixed waste in the samemanner as previously described for this class of oxidizing agents.

Alkaline Electrolytes

In one preferred embodiment, a cost reduction is achieved in the basicMEO process by using an alkaline electrolyte, such as but not limited toaqueous solutions of NaOH or KOH with mediator species wherein thereduced form of said mediator redox couple displays sufficientsolubility in said electrolyte to allow the desired oxidation of themixed waste to proceed at a practical rate. The oxidation potential ofredox reactions producing hydrogen ions (i.e., both mediator species andmixed waste and/or transuranic/actinides molecules reactions) areinversely proportional to the electrolyte pH, thus with the properselection of a redox couple mediator, it is possible, by increasing theelectrolyte pH, to minimize the electric potential required to affectthe desired oxidation process, thereby reducing the electric powerconsumed per unit mass of mixed waste and/or transuranic/actinidesprocessed.

When an alkaline anolyte (e.g., NaOH, KOH, etc.) is used, benefits arederived from the saponification (i.e., base promoted ester hydrolysis)of fatty acids to form water soluble alkali metal salts of the fattyacids (i.e., soaps) and glycerin, a process similar to the production ofsoap from animal fat by introducing it into a hot aqueous lye solution.

In this invention, when an alkaline anolyte is used, the CO₂ resultingfrom oxidation of the mixed waste and/or transuranic/actinides reactswith the anolyte to form alkali metal bicarbonates/carbonates. Thebicarbonate/carbonate ions circulate within the anolyte where they arereversibly oxidized to percarbonate ions either by anodic oxidationwithin the electrochemical cell or alternately by reacting with theoxidized form of a more powerful redox couple mediator, when present inthe anolyte. The carbonate thus functions exactly as a simple anionredox couple mediator, thereby producing an oxidizing species from themixed waste oxidation products that it is capable of destroyingadditional organic components of the mixed waste.

Additional MEO Electrolyte Features

In one preferred embodiment of this invention, the catholyte and anolyteare discrete entities separated by a membrane, thus they are notconstrained to share any common properties such as electrolyteconcentration, composition, or pH (i.e., acid, alkali, or neutral). Theprocess operates over the temperature range from approximately 0° C. toslightly below the boiling point of the electrolyte used during thedestruction of the mixed waste and/or transuranic/actinides.

MEO Process Augmented by Ultraviolet/Ultrasonic Energy

Decomposition of the hydrogen peroxide into free hydroxyl radicals iswell known to be promoted by ultraviolet (UV) irradiation. Thedestruction rate of mixed waste and/or transuranic/actinides obtainedusing the MEO process in this invention, therefore, is increased by UVirradiation of the reaction chamber anolyte to promote formation ofadditional hydroxyl free radicals. In a preferred embodiment, UVradiation is introduced into the anolyte chamber using a UV sourceeither internal to or adjacent to the anolyte chamber. The UVirradiation decomposes hydrogen peroxide, which is produced by secondaryoxidizers generated by the oxidized form of the mediator redox couple,into hydroxyl free radical. The result is an increase in the efficiencyof the MEO process since the energy expended in hydrogen peroxidegeneration is recovered through the oxidation of mixed waste and/ortransuranic/actinides materials in the anolyte chamber.

Additionally, ultrasonic energy is introduced into the anolyte chamber.Implosion of the microscopic bubbles formed by the rapidly oscillatingpressure waves emanating from the sonic horn generate shock wavescapable of producing extremely short lived and localized conditions of4800° C. and 1000 atmospheres pressure within the anolyte. Under theseconditions water molecules decompose into hydrogen atoms and hydroxylradicals. Upon quenching of the localized thermal spike, the hydroxylradicals undergo the aforementioned reactions with the mixed waste orcombine with each other to form another hydrogen peroxide molecule whichthen itself oxidizes additional mixed waste and/ortransuranic/actinides.

In another preferred embodiment, the destruction rate of non-anolytesoluble mixed waste is enhanced by affecting a reduction in thedimensions of the individual second (i.e., mixed waste) phase entitiespresent in the anolyte, thereby increasing the total waste and/ortransuranic/actinides surface area wetted by the anolyte and thereforethe amount of waste and/or transuranic/actinides oxidized per unit time.Immiscible liquids may be dispersed on an extremely fine scale withinthe aqueous anolyte by the introduction of suitable surfactants oremulsifying agents. Vigorous mechanical mixing such as with a colloidmill or the microscopic scale mixing affected by the aforementionedultrasonic energy induced microscopic bubble implosion could also beused to affect the desired reduction in size of the individual secondphase waste and/or transuranic/actinides volumes dispersed in theanolyte. The vast majority of solid mixed waste and/ortransuranic/actinides may be converted into a liquid phase, thusbecoming treatable as above, using a variety of cell disruptionmethodologies. Examples of these methods are mechanical shearing usingvarious rotor-stator homogenizers and ultrasonic devices (i.e.,sonicators) where the aforementioned implosion generated shock wave,augmented by the 4800° C. temperature spike, mixes the liquid and solidsfor better access to the oxidizers. Since water is a product of theoxidation process it requires no further energy to dispose of the mixedwaste thus saving energy that would be expended in a thermal basedprocess.

In another preferred embodiment, increasing the surface area exposed tothe anolyte enhances the destruction rate of non-anolyte solid mixedwaste and/or transuranic/actinides. The destruction rate for any givenconcentration of oxidizer in solution in the anolyte is limited to thearea of the solid with which the oxidizer can make contact. Theembodiment used for solids contains a mechanism for multiply puncturingthe solid when it is placed in the anolyte reaction chamber basket. Thepunctures allow the oxidizer to penetrate into the interior of the solidand increase the rate of destruction.

If the amount of water released directly from the mixed waste and/orformed as a reaction product from the oxidation of hydrogenous wastedilutes the anolyte to an unacceptable level, the anolyte can easily bereconstituted by simply raising the temperature and/or lowering thepressure in an optional evaporation chamber to affect removal of therequired amount of water. The soluble constituents of the mixed wasteand/or transuranic/actinides are rapidly dispersed throughout theanolyte on a molecular scale while the insoluble constituents aredispersed throughout the anolyte as an extremely fine second phase usingany of the aforementioned dispersal methodologies, thereby vastlyincreasing the mixed waste and/or transuranic/actinides anolyteinterfacial contact area beyond that possible with an intact solidconfiguration and thus increasing the rate at which the mixed wasteand/or transuranic/actinides is destroyed and the MEO efficiency.

In another preferred embodiment, increasing the surface area exposed tothe anolyte enhances the destruction rate of non-anolyte solid mixedwaste and/or transuranic/actinides. The destruction rate for any givenconcentration of oxidizer in solution in the anolyte is limited to thearea of the solid with which the oxidizer can make contact. Theembodiment used for solids contains a mechanism for multiply puncturingthe solid when it is placed in the anolyte reaction chamber basket. Thepunctures allow the oxidizer to penetrate into the interior of the solidby-passing difficult to destroy surface layers and increase the rate ofdestruction.

MEO Process Augmented with Free Radicals

The principals of the oxidation process used in this invention in whicha free radical (e.g., .O₂H, .OH, .SO₄, .NO₃,) cleaves and oxidize themixed waste and/or transuranic/actinides resulting in the formation ofsuccessively smaller hydrocarbon compounds. The intermediate compoundsso formed are easily oxidized to carbon dioxide and water duringsequential reactions.

Inorganic radicals are generated in aqueous solution variants of the MEOprocess in this invention. Radicals have been derived from carbonate,azide, nitrite, nitrate, phosphate, phosphite, sulphite, sulphate,selenite, thiocyanate, chloride, bromide, iodide and formate ions. TheMEO process may generate organic free radicals, such as sulfhydryl. Whenthe MEO process in this invention is applied to mixed waste materialsthey are broken down into organic compounds that are attacked by theaforementioned inorganic free radicals, producing organic free radicals,which contribute to the oxidation process and increase the efficiency ofthe MEO process.

These and further and other objects and features of the invention areapparent in the disclosure, which includes the above and ongoing writtenspecification, with the characteristics and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A MEO Apparatus Diagram is a schematic representation of a systemfor destroying mixed waste and/or the dissolution oftranuranics/actinides materials. FIG. 1A is a representation of ageneral embodiment of the present invention (with the understanding thatnot all of the components shown therein must necessarily be employed inall situations) and others may be added as needed for a particularapplication.

FIG. 1B Anolyte Reaction Chamber for Liquids, Mixtures, SmallParticulate and with Continuous Feed is a schematic representation ofthe anolyte reaction chamber used for destruction of mixed waste and/ordissolution of transuranic/actinides fluids, and mixtures which includesmall particulate. The anolyte reaction chamber is used for dissolutionof transuranics/actinides (such as a mixed oxide, nitride or carbideand/or mixture of oxides, nitrides or carbides of uranium and plutonium)totally dissolving them into solution. This chamber accommodates acontinuous feed of these materials into the chamber.

FIG. 1C Anolyte Reaction Chamber for Solids, Mixtures, and LargerParticulate and with Batch Operation is a schematic representation ofthe anolyte reaction chamber used for destruction of mixed waste solids,and mixtures that include large particulate. This chamber may be usedfor batch mode processing of mixed waste and/or dissolution oftransuranic/actinides.

FIG. 1D Anolyte Reaction Chamber Remote is a schematic representation ofthe anolyte reaction chamber used for destruction of mixed waste and/ordissolution of transuranic/actinides where the anolyte reaction chamberis separated from the basic MEO apparatus. This configuration allows thechamber to be a part of production line or similar use.

FIG. 1E Storage Container Used as Anolyte Reaction Chamber is aschematic representation of an anolyte reaction chamber that is acontainer contaminated with transuranic/actinides. The MEO process willdecontaminate this type of equipment, instruments, glassware, andcontainers (such as 50 gallon drums) by destroying the mixed waste anddissolving the transuranic/actinides. This configuration is used todecontaminate items and clean them for future use or disposal.

FIG. 2 MEO System Model 5.b is a schematic representation of a preferredembodiment using the FIG. 1B anolyte reaction chamber configuration. TheModel 5.b uses the anolyte reaction chamber 5 a in the MEO apparatusdepicted in FIG. 1A. This model is used for mixed waste and/ortransuranic/actinides fluids, and mixtures which include smallparticulate.

FIG. 3 MEO Controller for System Model 5.b is a schematic representationof the MEO electrical and electronic systems. FIG. 3 is a representationof a general embodiment of a controller for the present invention (withthe understanding that not all of the components shown therein mustnecessarily be employed in all situations) and others may be added asneeded for a particular application.

FIG. 4 MEO System Model 5.b Operational Steps is a schematicrepresentation of the generalized steps of the process used in the MEOapparatus System Model 5.b (with the understanding that not all of thecomponents shown therein must necessarily be employed in all situations)and others may be added as needed for a particular application.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

MEO Chemistry

Mediated Electrochemical Oxidation (MEO) process chemistry described inthis patent uses oxidizer species as described in Table I (simple anionsredox couple mediators); Type I IPAs formed by Mo, W, V, Nb, Ta, ormixtures there of as addenda atoms; Type I HPAs formed by incorporationinto the aforementioned IPAs of any of the elements listed in Table II(heteroatoms) either singly or in combination there of; or any HPAcontaining at least one heteroatom type (i.e., element) contained inboth Table I and Table II; or combinations of mediator species from anyor all of these generic groups. Since the anolyte and catholyte arecompletely separated entities, it is not necessary for both systems tocontain the same electrolyte. Each electrolyte may, independent of theother, consist of an aqueous solution of acids, typically but notlimited to nitric, sulfuric, of phosphoric; alkali, typically but notlimited to sodium or potassium hydroxide; or neutral salt typically butnot limited to sodium or potassium salts of the aforementioned strongmineral acids.

The MEO Apparatus is unique in that it accommodates the numerous choicesof mediator ions and electrolytes by simply draining, flushing, andrefilling the system with the mediator/electrolyte system of choice.

Because of redundancy and similarity in the description of the variousmediator ions, only the iron and nitric acid combination is discussed indetail. However, it is to be understood that the following discussion ofthe ferric/ferrate, (Fe⁺³)/(FeO₄ ⁻²) redox couple reaction in nitricacid (HNO₃) also applies to all the aforementioned oxidizer species andelectrolytes described at the beginning of this section. Furthermore,the following discussions of the interaction of ferrate ions withaqueous electrolytes to produce the aforementioned free radicals alsoapplies to all aforementioned mediators having an oxidation potentialsufficient to be classified super oxidizers (SO). An SO has an oxidationpotential at least equal to that of the redox couple Ce⁺³/Ce⁺⁴ which hasa potential of approximately 1.7 volts at 1 molar, 25° C. and pH 1 in anacid electrolyte.

FIG. 1A shows a MEO Apparatus in a schematic representation foroperating in the three modes (dissolution, destruction, anddecontamination) on mixed waste and/or transuranic/actinides.

At the anode of the electrochemical cell 25 Fe(III) ions (Fe⁺³, ferric)are oxidized to Fe(VI) ions (FeO₄ ⁻², ferrate),Fe⁺³+4H₂O→FeO₄ ⁻²+8H⁺+3e ⁻

If the anolyte temperature is sufficiently high, typically above 50° C.,the Fe(VI) species may undergo a redox reaction with the water in theaqueous anolyte. The oxidation of water proceeds by a sequence ofreactions producing a variety of intermediate reaction products, some ofwhich react with each other. A few of these intermediate reactionproducts are highly reactive free radicals including, but not limited tothe hydroxyl (.OH) and hydrogen peroxy or perhydroxyl (.HO₂) radicals.Additionally, the mediated oxidizer species ions may interact withanions present in the acid or neutral salt electrolyte (e.g., NO₃ ⁻, SO₄⁻², or PO₄ ⁻³, etc.) to produce free radicals typified by, but notlimited to .NO₃, or the anions may undergo direct oxidation at the anodeof the cell. The population of hydroxyl free radicals may be increasedby ultraviolet irradiation of the anolyte (see ultraviolet source 11) inthe reaction chambers 5(a,b,c) and buffer tank 20 to cleave the hydrogenperoxide molecules, and intermediate reaction products, into two suchradicals. Free radical populations also be increased by ultrasonicvibration (see ultrasonic source 9) induced by the aforementionedimplosion generated shock wave, augmented by the 4800° C. temperaturespike and 1000 atmospheres pressure.

These secondary oxidation species are capable of oxidizing mixed wasteand/or transuranic/actinides materials and thus act in consort withFe(VI) ions to oxidize the mixed waste and/or transuranic/actinidesmaterials.

The mediator oxidizing species reacts in the anolyte to produce thesecondary oxidizer species (free radicals). The free radical generatedreacts with and oxidizes a reductant. When the mixed waste hashalogenated hydrocarbons (such as solvents) in the mixture they reactwith the reductants. The reductants are strong reducing agents and theyreduce the halogenated hydrocarbons which results in theirdehalogenation. The reduced halogens remain in solution as halogen ions,since Table I offer alternative oxidizers to those previously used suchas silver which would precipitate. The remaining hydrocarbon moleculesare oxidized to CO₂ and water. Typical of this process is the removal ofthe chlorine from halogen hydrocarbons such as PCBs. The chlorineremains in solution and the remaining hydrocarbon molecules are furtherdecomposed into CO₂ and water. A resin column to avoid any release intothe atmosphere may be used to remove the chlorine. The oxidizing speciesis chosen from Table I so as to avoid the forming of participates suchas silver chloride. An example of a suitable oxidizer from Table I wouldbe the selection of the iron oxidizer being discussed in the foregoingparagraphs.

The oxidizers react with the mixed waste to produce CO₂ and water. Theseprocesses occur in the anolyte on the anode side of the system in thereaction chambers 5(a,b,c,d), buffer tank 20, and throughout the anolytesystem when in solution. Addition of ferric ions to non-iron-based MEOsystems are also proposed as this has the potential for increasing theoverall rate of mixed waste and/or transuranic/actinides oxidationcompared to the non-iron MEO system alone. (Again it is to be understoodthis discussion of the ferric/ferrate redox couple also applies to allthe aforementioned oxidizer species described at the beginning of thissection.) An example is considering the two step process of first ofwhich is to electrochemically forming a FeO₄ ⁻² ion. In the second stepis the FeO₄ ⁻² ion oxidizes a mediator ion, from its reduced form (e.g.,sulfate) to its oxidized form (e.g., peroxysulfate), faster than by thedirect anodic oxidation of the sulfate ion itself. Thus there is anoverall increase in the rate of mixed waste and/or transuranic/actinidesdestruction.

Membrane 27 separates the anode and the cathode chambers in theelectrochemical cell 25. Hydrogen ions (H⁺) or hydronium ions (H₃O⁺)travel through the membrane 27 due to the electrical potential from thedc power supply 29 applied between the anode(s) 26 and cathodes(s) 28.In the catholyte the nitric acid is reduced to nitrous acid3HNO₃+6H⁺+6e ⁻→3HNO₂+H₂Oby the reaction between the H⁺ ions and the nitric acid. Oxygen isintroduced into the catholyte through the air sparge 37 located belowthe liquid surface, and the nitric acid is regenerated,3HNO₂+3/2O₂→3HNO₃

In the case where the catholyte contain compounds other then nitrogensuch as sulfuric or phosphoric acids or their salts, the hydrogen ions(H⁺) or hydronium ions (H₃O⁺) contact the cathode and hydrogen gasevolves. The hydrogen gas is diluted with the air from the air spargeand released to the atmosphere or the evolved hydrogen gas can be feedto devices that use hydrogen as a fuel such as the fuel cells. Thehydrogen may under go purification prior to use (e.g., palladiumdiffusion, etc.) and/or solid state storage (e.g., adsorption inzirconium, etc.).

In some cases oxygen is evolved at the anode due to the over voltagenecessary to create the oxidation species of some of the mediator ions.The efficiency of these mediators is somewhat less under thoseconditions. The evolved oxygen can be feed to the devices that usehydrogen as a fuel such as the fuel cells. Using the evolved oxygen toenrich the air above its nominal oxygen content of 20.9 percentincreases the efficiency of fuel cells deriving their oxygen supply fromambient air.

The overall MEO process may be operate in three different modes(dissolution, destruction, and decontamination). In the first mode(dissolution) the process runs until the transuranics (such as a mixedoxides or carbides, mixture of oxides or carbides of uranium andplutonium, etc.) are totally dissolved into solution. The transuranicmaterials are usually in form of powder or powder in solution.

The second mode (destruction) the process is operated such that themixed waste materials are reduced to CO₂, water and small amounts ofinorganic salts. These mixed waste materials are composed of any itemthat has been used in connection with radioactive materials and havebecome contaminated (e.g., clothing, rags, absorbents, etc.).

The third mode (decontamination) involves contaminated equipment,instruments, glassware, containers (such as 50 gallon drums) andmaterials. In this mode the MEO process destroys the mixed wastematerials that have contaminated them. FIG. 1E is typical of this use.These items are used as an anolyte reaction chamber and the electrolytecontaining the oxidizing species is introduced into them. The MEOprocess cleans the contaminated items rendering them non-toxic and safeto reuse or dispose of them.

In modes two and three the mixed waste is converted to carbon dioxide,water, and a small amount of inorganic compounds and/ortransuranic/actinides in solution or as a precipitate, which may beextracted by the inorganic compound removal and treatment system 15. TheMEO process will proceed until complete destruction of the mixed wasteand the dissolving of the transuranic/actinides on contaminatedequipment, instruments, glassware, containers (such as 50 gallon drums)and materials.

Each of the following patent(s)/co-pending applications are incorporatedherein by reference in their entireties:

U.S. Pat. No. 6,402,932 issued Jun. 11, 2002.

U.S. application Ser. No 10/263,810 filed Oct. 4, 2002.

U.S. application Ser. No 10/127,604 filed Apr. 23, 2002.

U.S. Provisional Application Ser. No. 60/409,202 filed Sep. 10, 2002.

U.S. Provisional Application Ser. No. 60/398,808 filed Jul. 29, 2002.

U.S. Provisional Application Ser. No. 60/398,808 filed Jul. 29, 2002.

PCT/US02/03249 filed Feb. 6, 2002.

PCT/US03/02151 based on U.S. Provisional Application Ser. No. 60/350,352filed Jan. 24, 2002.

PCT/US03/02152 based on U.S. Provisional Application Ser. No. 60/350,377filed Jan. 24, 2002.

PCT/US03/02153 based on U.S. Provisional Application Ser. No. 60/350,378filed Jan. 24, 2002.

PCT/US03/13051 based on U.S. Provisional Application Ser. No. 60/375,430filed Apr. 26, 2002.

PCT/US03/04065 filed Feb. 12, 2003.

PCT/US02/33732 based on U.S. Provisional Application Ser. No. 60/330,436filed Oct. 22, 2001.

PCT/US02/32040 based on U.S. Provisional Application Ser. No. 60/327,306filed Oct. 9, 2001.

These and further and other objects and features of the invention areapparent in the disclosure, which includes the above and ongoing writtenspecification, with the drawings.

MEO Apparatus

A schematic drawing of the MEO apparatus shown in FIG. 1A MEO ApparatusDiagram illustrates the application of the MEO process to all threemodes of operation; dissolution, destruction and decontamination. FIGS.1B through 1F illustrate typical anolyte reaction chambers that may beused will the overall system in FIG. 1A. There are numerous combinationsof five anolyte reaction chambers and three modes of operation.

The bulk of the anolyte resides in the anolyte reaction chambers5(a,b,c,d) and the buffer tank 20. In the case where the mixed waste issolids, liquids and large particles in suspension, the chamber isaccessed by raising the Lid 1 The anolyte portion of the electrolytesolution contains for example Fe⁺³/FeO₄ ⁻² redox couple anions andsecondary oxidizing species (e.g., free radicals, H₂O₂, etc.).

The MEO apparatus is composed of two separate closed-loop systemscontaining an electrolyte solution composed of anolyte and catholytesolutions. The anolyte and catholyte solutions are contained in theanolyte (A) system and the catholyte (B) system, respectively. These twoclosed-loop systems are discussed in detail in the following paragraphs.

ANOLYTE SYSTEM (A)

Referring to FIG. 1A, the mixed waste and/or transuranic/actinides maybe a liquid, solid, a mixture of solids and liquids, or combined wasteand/or transuranic/actinides. FIGS. 1B through 1E provide preferredembodiments of the anolyte reaction chambers 5 a through 5 d and buffertank 20.

The anolyte reaction chamber 5 a in FIG. 1B is designed for liquids,mixtures, and small particulate and introduced in a continuous feedmode. The mixed waste and/or transuranic/actinides is introduced intothe anolyte reaction chamber 5 a by input pump 10 through the Lid 1 intoanolyte reaction chamber 5 a. The apparatus continuously circulates theanolyte portion of the electrolyte directly from the electrochemicalcell 25 through the anolyte reaction chamber 5 a to maximize theconcentration of oxidizing species contacting the waste and/ortransuranic/actinides. The anolyte is introduced into the anolytereaction chamber 5 a through the spray head 4(a) and stream head 4(b).The two heads are designed to increase the exposure of the mixed wasteand/or transuranic/actinides to the anolyte by enhancing the mixing inthe anolyte reaction chamber 5 a. Introducing the anolyte into theanolyte reaction chamber 5 a as a spray onto the anolyte surfacepromotes contact with (i.e., oxidation of) any immiscible organicsurface layers present. A filter 6 is located at the base of thereaction chamber 5 a to limit the size of the solid particles toapproximately 1 mm in diameter (i.e., smaller that the minimum dimensionof the anolyte flow path in the electrochemical cell 25) therebypreventing solid particles large enough to clog the electrochemical cell25 flow paths from exiting the reaction chamber 5 a. Contact of theoxidizing species with incomplete oxidation products that are gaseous atthe conditions within the reaction chamber 5 a may be further enhancedby using conventional techniques for promoting gas/liquid contact (e.g.,ultrasonic vibration 9, mechanical mixing 7). An ultraviolet source 11is introduced into the anolyte reaction chamber 5 a to decompose thehydrogen peroxide formed by the MEO process into free hydroxyl radicals.

The anolyte reaction chamber 5 b in FIG. 1C is designed for solids,mixtures and batch operations. The hinged lid 1 is lifted, and the topof the basket 3 is opened. The mixed waste and/or transuranic/actinidesis introduced into the basket 3 in the anolyte reaction chamber 5 bwhere the solid waste and/or transuranic/actinides remains while theliquid portion of the waste and/or transuranic/actinides flows into theanolyte. The basket 3 top is closed and the basket 3 is lowered by alever 36 connected to the lid 1 into the anolyte such that all itscontents are held submerged in the anolyte throughout the oxidizationprocess. Lid 1 has a seal around the opening and it is locked beforeoperation begins.

A mechanical device (penetrator 34) is incorporated into the basket 3that create multiple perforations in the outer layers of the solid mixedwaste and/or transuranic/actinides so that the anolyte can penetrateinto the waste and/or transuranic/actinides. This penetration speeds upthe oxidation of the solid mixed waste and/or transuranic/actinides byincreasing the surface area exposed to the anolyte oxidizer, andallowing said oxidizer immediate access to portions of theaforementioned waste and/or transuranic/actinides that are encased in(i.e., protected by) more difficult to oxidize surrounding outer layers.

The apparatus continuously circulates the anolyte portion of theelectrolyte directly from the electrochemical cell 25 through theanolyte reaction chamber 5 b to maximize the concentration of oxidizingspecies contacting the waste and/or transuranic/actinides. The anolyteenters the anolyte reaction chamber 5 b and is injected through twonozzles; one a spray head to distribute the anolyte throughout theanolyte reaction chamber 5 b, and the second is a stream head to promotecirculation and turbulence in the anolyte in the chamber. Introducingthe anolyte into the anolyte reaction chamber 5 b as a spray onto theanolyte surface promotes contact with (i.e., oxidation of) anyimmiscible organic surface layers present. A filter 6 is located at thebase of the anolyte reaction chamber 5 b to limit the size of the solidparticles to approximately 1 mm in diameter (i.e., smaller that theminimum dimension of the anolyte flow path in the electrochemical cell25) thereby preventing solid particles large enough to clog theelectrochemical cell 25 flow paths from exiting the anolyte reactionchamber 5 b. Contact of the oxidizing species with incomplete oxidationproducts that are gaseous at the conditions within the anolyte reactionchamber 5 b may be further enhanced by using conventional techniques forpromoting gas/liquid contact (e.g., ultrasonic vibration 9, mechanicalmixing 7). An ultraviolet source 11 is introduced into the anolytereaction chamber 5 b to decompose the hydrogen peroxide formed by theMEO process into free hydroxyl radicals.

The anolyte reaction chamber 5 c in FIG. 1D is designed to use ananolyte reaction chamber that is exterior to the basic MEO apparatus.Typical of this configuration is an apparatus that is similar to anultrasonic bath. The anolyte reaction chamber 5 c may be integrated intoa production process to be used to destroy halogenated hydrocarbons as apart of the process. The anolyte reaction chamber 5 c may be connectedto the basic MEO apparatus through tubing and a pumping system. Theanolyte is pumped from the buffer tank 20 in the basic MEO apparatus bythe pump 8 where it is introduced into the anolyte reaction chamber 5 cthrough spray head 4(a) as a spray onto the anolyte surface therebypromoting contact with (i.e., oxidation of) any immiscible organicsurface layers present in addition to reacting with (i.e., oxidizing)the mixed waste and/or transuranic/actinides dissolved, suspended orsubmerged within the anolyte in the anolyte reaction chamber 5 c. Theinlet to pump 8 is protected by an in-line screen filter 6 whichprevents solid particles large enough to clog the spray head 4(a) fromexiting the buffer tank 20. Contact of the oxidizing species withincomplete oxidation products that are gaseous at the conditions withinthe anolyte reaction chamber 5 c may be further enhanced by usingconventional techniques for promoting gas/liquid contact (e.g.,ultrasonic vibration 9, mechanical mixing 7). An ultraviolet source 11is introduced into the anolyte reaction chamber 5 c to decompose thehydrogen peroxide formed by the MEO process into free hydroxyl radicals.The input pump 10 pumps the anolyte and mixed waste and/ortransuranic/actinides liquid in the anolyte reaction chamber 5 c back tothe buffer tank in the basic MEO apparatus through a return tubeprotected by an in-line screen filter 6 which prevents solid particleslarge enough to clog the spray head 4(a) from exiting the anolytereaction chamber 5 c. A third tube is connected to the anolyte reactionchamber 5 c to pump out any gas that is present from the originalcontents or from the MEO process. The gas is pumped by the air pump 32.The return gas tube is submerged in the buffer tank 20 in the basic MEOsystem so as to oxidize any volatile organic compounds in the gas to CO₂before release to the gas cleaning system 16. Contact of the oxidizingspecies with incomplete oxidation products that are gaseous at theconditions within the anolyte reaction chamber 5 c may be furtherenhanced by using conventional techniques for promoting gas/liquidcontact (e.g., ultrasonic vibration 9, mechanical mixing 7). Theapparatus continuously circulates the anolyte portion of the electrolytedirectly from the electrochemical cell 25 through the buffer tank 20 tomaximize the concentration of oxidizing species contacting the wasteand/or transuranic/actinides.

The hinged lid 1 is lifted, and the top of the basket 3 is opened. Themixed waste and/or transuranic/actinides is introduced into thewastebasket 3 in the anolyte reaction chamber 5 c where the solid wasteand/or transuranic/actinides remains while the liquid portion of thewaste and/or transuranic/actinides flows into the anolyte. The basket 3top and the lid 1 are closed and lid 1 has a seal around the opening andit is locked before operation begins. With basket 3 lid closed, thebasket 3 is lowered into the anolyte so that all it contents are heldsubmerged in the anolyte throughout the oxidization process.

A mechanical device (penetrator 34) may be incorporated into the basket3 in the anolyte reaction chamber 5 c that create multiple perforationsin the outer portion of the solid mixed waste and/ortransuranic/actinides so that the anolyte can rapidly penetrate into theinterior of the waste and/or transuranic/actinides. The penetrator 34serves the same purpose it does in the anolyte reaction chamber 5 bdescribed in the foregoing section. A filter 6 is located at the base ofthe buffer tank 20 to limit the size of the solid particles toapproximately 1 mm in diameter (i.e., smaller that the minimum dimensionof the anolyte flow path in the electrochemical cell 25) therebypreventing solid particles large enough to clog the electrochemical cell25 flow paths from exiting the buffer tank (20).

The anolyte reaction chamber 5 d in FIG. 1E is designed to use a closedcontainer exterior to the basic apparatus as the anolyte reactionchamber. FIG. 1E illustrates one example of an exterior container, whichin this case is a metal vessel such as a 50 gallon storage drumcontaining mixed waste and/or transuranic/actinides. A similar systemmay be applied to a larger buried storage tank with the same results.

The drum may be connected to the basic MEO apparatus through tubing anda pumping system. The anolyte is pumped by the pump 8 from the buffertank 20 in the basic MEO apparatus into the anolyte reaction chamber 5 dwhere it reacts with the contents and oxidizes the mixed waste and/ortransuranic/actinides. The anolyte stream is oscillated within theanolyte reaction chamber 5 d to allow for thorough mixing and forcleaning of the walls of the anolyte reaction chamber. The input pump 10pumps the anolyte and mixed waste and/or transuranic/actinides liquid inthe anolyte reaction chamber 5 d back to the buffer tank in the basicMEO apparatus through a return tube protected by an in-line screenfilter 6 which prevents solid particles large enough to clog the sprayhead 4(a) from exiting the anolyte reaction chamber 5 d. A third tube isconnected to the reaction chamber 5 d through the air pump 32 to pumpout any gas that is present from the original contents or from the MEOprocess. The return gas tube is submerged below the anolyte level in thebuffer tank 20 in the basic MEO system so as to oxidize any volatileorganic compounds in the gas to CO₂ before release to the gas cleaningsystem 16.

The anolyte from the electrochemical cell 25 is introduced into thebuffer tank 20 through the spray head 4(a) and stream head 4(b). The twoheads are designed to increase the exposure of the mixed waste and/ortransuranic/actinides to the anolyte by enhancing the mixing in theanolyte reaction chambers. Introducing the anolyte into the buffer tank20 as a spray onto the anolyte surface promotes contact with (i.e.,oxidation of) any immiscible halogenated hydrocarbon surface layerspresent.

The MEO apparatus continuously circulates the anolyte portion of theelectrolyte directly from the electrochemical cell 25 into the buffertank 20 to maximize the concentration of oxidizing species contactingthe waste and/or transuranic/actinides. A filter 6 is located at thebase of the buffer tank to-limit the size of the solid particles toapproximately 1 mm in diameter (i.e., smaller than the minimum dimensionof the anolyte flow path in the electrochemical cell 25). Contact of theoxidizing species with incomplete oxidation products that are gaseous atthe conditions within the buffer tank 20 may be enhanced by usingconventional techniques for promoting gas/liquid contact (e.g.,ultrasonic vibration 9, mechanical mixing 7). An ultraviolet source 11is introduced into the buffer tank 20 to decompose the hydrogen peroxideformed by the MEO process into free hydroxyl radicals.

All surfaces of the apparatus in contact with the anolyte are composedof stainless steel, glass, or nonreactive polymers (e.g.,polytetrafluoroethylene (PTFE), PTFE lined tubing, etc), PTFE coatedmetallic tubing, glazed ceramic, glazed metallic, and glazed compositefrom metallurgic isostatic pressing. These materials provide an anolytecontainment boundary to protect the components of the MEO apparatus frombeing oxidized by the electrolyte.

The anolyte circulation system contains a pump 19 and a removal andtreatment system 15 (e.g., filter, centrifuge, hydrocyclone, etc,) toremove any insoluble inorganic compounds that form as a result ofmediator or electrolyte ions reacting with anions of or containinghalogens, sulfur, phosphorous, nitrogen, etc. that may be present in thewaste and/or transuranic/actinides stream thus preventing formation ofunstable compounds (e.g., perchlorates, etc.). The anolyte is thenreturned to the electrochemical cell 25, where the oxidizing species areregenerated, which completes the circulation in the anolyte system (A).

The residue of the inorganic compounds is flushed out of the treatmentsystem 15 during periodic maintenance if necessary. If warranted, theinsoluble inorganic compounds are converted to water-soluble compoundsusing any one of several chemical or electrochemical processes.

Waste and/or transuranic/actinides is added to the anolyte reactionchambers 5(a,b,c,d) either continuously or in the batch mode dependingon the anolyte reaction configuration chosen.

The MEO system apparatus incorporates two methods that may control therate of destruction of mixed waste and/or dissolution of thetransuranic/actinides and control the order of which halogenatedhydrocarbon molecular bonds are broken. In first method the anolytetemperature is initially at or below the operating temperature andsubsequently increased by the thermal controls 21 and 22 until thedesired operating temperature for the specific waste and/ortransuranic/actinides stream is obtained. In the second method the mixedwaste and/or transuranic/actinides is introduced into the apparatus,with the concentration of electrochemically generated oxidizing speciesin the anolyte being limited to some predetermined value between zeroand the maximum desired operating concentration for the waste stream bycontrolling of the electric current in the electrochemical cell 25 withthe dc power supply 29 and subsequently increased to the desiredoperating concentration. These two methods can be used in combination.

The electrolyte is composed of an aqueous solution of mediator speciesand electrolytes appropriate for the species selected and is operatedwithin the temperature range from approximately 0° C. to slightly belowthe boiling point of the electrolytic solution, usually less then 100°C., at a temperature or temperature profile most conducive to thedesired mixed waste destruction rate (e.g., most rapid, most economical,etc.). The acid, alkaline, or neutral salt electrolyte used isdetermined by the conditions in which the species may exist.

Considerable attention has been paid to halogens, especially chlorineand their deleterious interactions with silver mediator ions, howeverthis is of much less concern or importance to this invention. The widerange of properties (e.g., oxidation potential, solubility of compounds,cost, etc.) of the mediator species claimed in this patent allowsselection of a single or mixture of mediators either avoiding formationof insoluble compounds, or easily recovering the mediator from theprecipitated materials, or being sufficiently inexpensive so as to allowthe simple disposal of the insoluble compounds as waste, while stillmaintaining the capability to oxidize (i.e., destroy) the mixed wasteeconomically.

The mixed waste destruction process may be monitored by severalelectrochemical and physical methods. First, various cell voltages(e.g., open circuit, anode vs. reference electrode, ion specificelectrode, etc.) yield information about the ratio of oxidized toreduced mediator ion concentrations which may be correlated with theamount of reducing agent (i.e., mixed waste and/ortransuranic/actinides) either dissolved in or wetted by the anolyte.Second, if a color change accompanies the transition of the mediatorspecies between it's oxidized and reduced states (e.g., heteropolyblues, etc.), the rate of decay of the color associated with theoxidized state, under zero current conditions, could be used as a grossindication of the amount of reducing agent (i.e., oxidizable wasteand/or transuranic/actinides) present. If no color change occurs in themediator, it may be possible to select another mediator to simply serveas the oxidization potential equivalent of a pH indicator. Such anindicator is required to have an oxidation potential between that of theworking mediator and the halogenated hydrocarbon, species, and a colorchange associated with the oxidization state transition.

The anolyte reaction chambers 5(a,b,c,d) off-gas consists of CO₂ and COfrom complete and incomplete combustion (i.e., oxidation) of thecarbonaceous material in the mixed waste, and possibly oxygen fromoxidation of water molecules at the anode. Standard anesthesiologypractice requires these three gases to be routinely monitored in realtime under operating room conditions, while many other respiratoryrelated medical practices also require real time monitoring of thesegases. Thus, a mature industry exists for the production of miniaturizedgas monitors directly applicable to the continuous quantitativemonitoring of anolyte off-gas for the presence of combustion products.Although usually not as accurate and requiring larger samples, monitorsfor these same gasses are used in the furnace and boiler serviceindustry for flue gas analysis.

The anolyte is circulated into the reaction chambers 5(a,b,c,d) throughthe electrochemical cell 25 by pump 19 on the anode 26 side of themembrane 27. A membrane 27 in the electrochemical cell 25 separates theanolyte portion and catholyte portion of the electrolyte.

Small thermal control units 21 and 22 are connected to the flow streamto heat or cool the anolyte to the selected temperature range. Ifwarranted a heat exchanger 23 can be located immediately upstream fromthe electrochemical cell 25 to lower the anolyte temperature within thecell to the desired level. Another heat exchanger 24 can be locatedimmediately upstream of the anolyte reaction chamber inlet to controlthe anolyte temperature in the reaction chamber to within the desiredtemperature range to affect the desired chemical reactions at thedesired rates.

The electrochemical cell 25 is energized by a DC power supply 29, whichis powered by the AC power supply 30. The DC power supply 29 is lowvoltage high current supply usually operating below 4V DC but notlimited to that range. The AC power supply 30 operates off a typical110v AC line for the smaller units and 240v AC for the larger units.

The oxidizer species population produced by electrochemical generation(i.e., anodic oxidation) of the oxidized form of the redox couplesreferenced herein can be enhanced by conducting the process at lowtemperatures, thereby reducing the rate at which thermally activatedparasitic reactions consume the oxidizer.

Reaction products resulting from the oxidation processes occurring inthe anolyte system (A) that are gaseous at the anolyte operatingtemperature and pressure are discharged to the condenser 13. The moreeasily condensed products of incomplete oxidation are separated in thecondenser 13 from the anolyte off-gas stream and are returned to theanolyte reaction chamber 5(a,b,c) or the buffer tank 20 for furtheroxidation. The non-condensable incomplete oxidation products (e.g., lowmolecular weight organics, carbon monoxide, etc.) are reduced toacceptable levels for atmospheric release by a gas cleaning system 16.The gas cleaning system 16 is not a necessary component of the MEOapparatus for the destruction of most types of mixed waste and/ordissolution of the transuranic/actinides.

If the gas cleaning system 16 is incorporated into the MEO apparatus,the anolyte off-gas is contacted in a counter current flow gas scrubbingsystem in the off-gas cleaning system 16 wherein the noncondensiblesfrom the condenser 13 are introduced into the lower portion of thecolumn through a flow distribution system of the gas cleaning system 16and a small side stream of freshly oxidized anolyte direct from theelectrochemical cell 25 is introduced into the upper portion of thecolumn. This results in the gas phase continuously reacting with theoxidizing mediator species as it rises up the column past the downflowing anolyte. Under these conditions the gas about to exit the top ofthe column may have the lowest concentration of oxidizable species andalso be in contact with the anolyte having the highest concentration ofoxidizer species thereby promoting reduction of any air pollutantspresent down to levels acceptable for release to the atmosphere.Gas-liquid contact within the column may be promoted by a number of wellestablished methods (e.g., packed column, pulsed flow, ultrasonicmixing, etc,) that does not result in any meaningful backpressure withinthe anolyte flow system. Anolyte exiting the bottom of thecountercurrent scrubbing column is discharged into the anolyte reactionchamber 5(a,b,c) or buffer tank 20 and mixed with the remainder of theanolyte. Unique waste and/or transuranic/actinides compositions mayresult in the generation of unusual gaseous products that could moreeasily be removed by more traditional air pollution technologies. Suchmethodologies could be used in series with the afore described system asa polishing process treating the gaseous discharge from thecountercurrent column, or if advantageous, instead of it. The majorproducts of the oxidation process are CO₂, and water (including minoramounts of Co and inorganic salts), where the CO₂ is vented 14 out ofthe system.

An optional inorganic compound removal and treatment systems 15 is usedshould there be more than trace amount of halogens, or other precipitateforming anions present in the mixed waste being processed, therebyprecluding formation of unstable oxycompounds (e.g., perchlorates,etc.).

The MEO process proceeds until complete destruction of the mixed wasteand/or the dissolution of the transuranic/actinides has been affected.

Catholyte System (B)

The bulk of the catholyte is resident in the catholyte reaction chamber31. All surfaces of the apparatus in contact with the catholyte arecomposed of acid and alkaline resistant materials. The catholyte portionof the electrolyte is circulated by pump 43 through the electrochemicalcell 25 on the cathode 28 side of the membrane 27. The catholyte portionof the electrolyte flows into a catholyte reservoir 31. Small thermalcontrol units 45 and 46 are connected to the catholyte flow stream toheat or cool the catholyte to the selected temperature range.

External air is introduced through an air sparge 37 into the catholytereservoir 31. In the case where nitrogen compounds (such as nitrates)are used in the catholyte, the oxygen contained in the air oxidizes anynitrous acid and the small amounts of nitrogen oxides (NO_(x)), producedby the cathode reactions. Contact of the oxidizing gas with nitrogencompounds (nitrous acid) may be enhanced by using conventionaltechniques for promoting gas/liquid contact such as ultrasonic vibration48, mechanical mixing 35, etc. Systems using non-nitric acid catholytesmay also require air sparging to dilute and remove off-gas such ashydrogen. An off-gas cleaning system 39 is used to remove any unwantedgas products (e.g. NO₂, etc.). The cleaned gas stream, combined with theunreacted components of the air introduced into the system is dischargedthrough the atmospheric vent 47.

Optional anolyte recovery system 41 is positioned on the catholyte side.Some mediator oxidizer ions may cross the membrane 27 and this option isavailable if it is necessary to remove them through the anolyte recoverysystem 41 to maintain process efficiency or cell operability, or theireconomic worth necessitates their recovery. Operating theelectrochemical cell 25 at higher than normal membrane 27 currentdensities (i.e., above about 0.5 amps/cm²) increases the rate of mixedwaste destruction and/or the dissolution of the transuranic/actinides,but also result in increased mediator ion transport through the membraneinto the catholyte. It may be economically advantageous for theelectrochemical cell 25 to be operated in this mode. It is advantageouswhenever the replacement cost of the mediator species orremoval/recovery costs are less than the cost benefits of increasing thewaste throughput (i.e., oxidation rate) of the electrochemical cell 25.Increasing the capitol cost of expanding the size of the electrochemicalcell 25 can be avoided by using this operational option.

MEO Controller

An operator runs an MEO Apparatus (FIG. 1A) by using an MEO Controller.FIG. 3 MEO Controller for System Model 5.b is used to depict a typicalcontroller such as would be used with MEO Apparatus (FIG. 1A). Thecontroller 49 with microprocessor is connected to a monitor 51 and akeyboard 53. The operator inputs commands to the controller 49 throughthe keyboard 53 responding to the information displayed on the monitor51. The controller 49 runs a program that sequences the steps for theoperation of the MEO apparatus. The program has pre-programmed sequencesof standard operations that the operator may follow or may choose hisown sequences of operations. The controller 49 allows the operator toselect his own sequences within limits that assure a safe and reliableoperation. The controller 49 sends digital commands that regulates theelectrical power (AC 30 and DC 29) to the various components in the MEOapparatus; pumps 19 and 43, mixers 7 and 35, thermal controls 21, 22,45, 46, ultraviolet sources 11, ultrasonic sources 9 and 48, CO₂ vent14, air sparge 37, and electrochemical cell 25. The controller receivescomponent response and status from the components. The controller sendsdigital commands to the sensors to access sensor information throughsensor responses. The sensors in the MEO apparatus provide digitalinformation on the state of the various components. Sensors measure flowrate 59, temperature 61, pH 63, CO₂, CO, O₂, venting 65, degree ofoxidation 67, air sparge sensor 69, etc. The controller 49 receivesstatus information on the electrical potential (voltmeter 57) across theelectrochemical cell, or individual cells if a multi-cell configuration,and between the anode(s) and reference electrodes internal to thecell(s) 25 and the current (ammeter 55) flowing between the electrodeswithin each cell.

Example System Model

A preferred embodiment, MEO System Model 5.b (shown in FIG. 2 MEO SystemModel 5.b) is sized for use for a small to mid-size application for thedestruction of solids and mixtures of solids and liquid mixed wasteand/or transuranic/actinides being batch feed. This embodiment depicts aconfiguration using the system apparatus presented in FIGS. 1A and 1C.Other preferred embodiments (representing FIGS. 1B, 1D, and 1E havedifferences in the external configuration and size but are essentiallythe same in internal function and components as depicted in FIGS. 1A and1C.

The preferred embodiment in FIG. 2 comprises a housing 72 constructed ofmetal or high strength plastic surrounding the electrochemical cell 25,the electrolyte and the foraminous basket 3. The AC power is provided tothe AC power supply 30 by the power cord 78. A monitor screen 51 isincorporated into the housing 72 for displaying information about thesystem and about the waste and/or transuranic/actinides being treated.Additionally, a control keyboard 53 is incorporated into the housing 72for inputting information into the system. The monitor screen 51 and thecontrol keyboard 53 may be attached to the system without incorporatingthem into the housing 72. In a preferred embodiment, status lights 73are incorporated into the housing 72 for displaying information aboutthe status of the treatment of the mixed waste and/ortransuranic/actinides material. An air sparge 37 is incorporated intothe housing 72 to allow air to be introduced into the catholyte reactionchamber 31 below the surface of the catholyte. In addition, a CO₂ vent14 is incorporated into the housing 72 to allow for CO₂ release from theanolyte reaction chamber 5 b via the gas cleaning system 16 housedwithin. In a preferred embodiment, the housing includes means forcleaning out the MEO waste treatment system, including a flush(s) 18 anddrain(s) 12 through which the anolyte and catholyte pass. The preferredembodiment further comprises an atmospheric vent 47 facilitating thereleases of gases into the atmosphere from the catholyte reactionchamber 31 via the gas cleaning system 39. Other preferred embodimentsystems are similar in nature but are scaled up in size to handle alarger capacity of waste, such as a incinerator replacement units.

The system has a control keyboard 53 for input of commands and data. TheOn/Off button 74 is used to turn the apparatus power on and off. Thereis a monitor screen 51 to display the systems operation and functions.Below the keyboard 53 and monitor screen 51 are the status lights 73 foron, off, and standby.

Mixed waste and/or transuranic/actinides is introduced into the anolytereaction chambers 5 b as depicted in FIGS. 1C. In the case of solid,mixtures, and batch feed operation, the hinged lid 1 is opened and themixed waste and/or transuranic/actinides is deposited in the basket 3 inthe anolyte reaction chamber 5 b. The top of basket 3 is closed and thebasket 3 is lowered so that the mixed waste and/or transuranic/actinidesis totally submerged in the anolyte. Lid 1 is closed and lid stop 2keeps the lid opening controlled. The hinged lid 1 is equipped with alocking latch 76 that is operated by the controller 49. A penetrator 34attached to the basket 3 punctures the solids in the basket 3 thusincreasing the surface area exposed to the oxidizer and providingmediator flow paths into the interior of the solid mixed waste and/ortransuranic/actinides.

In the anolyte reaction chamber 5 b is the aqueous acid, alkali, orneutral salt electrolyte and mediated oxidizer species solution in whichthe oxidized form of the mediator redox couple initially may be presentor may be generated electrochemically after introduction of the mixedwaste and/or transuranic/actinides and application of DC power 29 to theelectrochemical cell 25. Similarly, the mixed waste and/ortransuranic/actinides may be introduced when the anolyte is at or belowroom temperature, operating temperature or some optimum intermediatetemperature. DC power supply 29 provides direct current to anelectrochemical cell 25. Pump 19 circulates the anolyte portion of theelectrolyte and the mixed waste and/or transuranic/actinides material israpidly oxidized at temperatures below 100° C. and at ambient pressure.An in-line filter 6 prevents solid particles large enough to clog theelectrochemical cell 25 flow paths from exiting this anolyte reactionchamber 5 b. The oxidation process continues to break the materials downinto smaller and smaller molecules until the products are CO₂, water,and some CO and inorganic salts. Any residue is pacified in the form ofa salt and may be periodically removed through the Inorganic CompoundRemoval and Treatment System 15 and drain outlets 12. The basic designof the MEO apparatus permits the user to change the type of electrolytewithout having to alter the equipment in the apparatus. The changing ofthe electrolyte is accomplished by using the drain(s) 12 and flush(s) 18or by opening the anolyte reaction chamber 5 b and catholyte reactionchamber 31 to introduce the electrolyte(s). The ability to change thetype of electrolyte(s) allows the user to tailor the MEO process todiffering mixed waste and/or transuranic/actinides properties. Thecatholyte reservoir 31 has a screwed top 33 (shown in FIG. 1A), whichallow access to the reservoir 31 for cleaning and maintenance by servicepersonnel.

The MEO process advantageous properties of low power consumption andvery low loses of the mediated oxidizer species and electrolyte, provideas an option for the device to be operated at a low power level duringthe day to achieve a'slow rate of destruction of the mixed waste and/orthe dissolution of the transuranic/actinides throughout the day. Whilethe MEO apparatus is in this mode, mixed waste and/ortransuranic/actinides is added as it is generated throughout the day andthe unit placed in full activation during non-business hours.

The compactness of the device makes it ideal small and mid-sizeapplications as well as being suitable for use with high volume inputsof industrial processes activities. The process operates at lowtemperature and ambient atmospheric pressure and does not generate toxiccompounds during the destruction of the mixed waste and/or dissolutionof the transuranic/actinides, making the process indoors compatible. Thesystem is scalable to a unit large enough to replace a hospitalincinerator system. The CO₂ oxidation product from the anolyte system Ais vented out the CO₂ vent 14. The off-gas products from the catholytesystem B is vented through the atmospheric air vent 47 as shown.

Steps of the Operation of the MEO System Model 5.b

The steps of the operation of the MEO process are depicted in FIG. 4 MEOSystem Model 5.b Operational Steps. These operational steps arepresented to illustrate the operation of one of the MEO apparatus' fromthe four configurations previously discussed for oxidizing the varioustypes of mixed waste. When other anolyte reaction chambers 5(a,c,d)configurations are used the series of steps would be similar to the onesfor FIG. 1C which covers solids, mixtures of solids and liquids beingprocessed in a batch feed mode.

This MEO apparatus is contained in the housing 72. The MEO system isstarted 81 by the operator engaging the ‘ON’ button 74 on the controlkeyboard 53. The system controller 49, which contains a microprocessor,runs the program that controls the entire sequence of operations 82. Themonitor screen 51 displays the steps of the process in the propersequence. The status lights 73 on the panel provide the status of theMEO apparatus (e.g. on, off, ready, standby).

The mixed waste and/or transuranic/actinides is introduced into theanolyte reaction chambers 5 b as depicted in FIGS. 1C. In the case ofsolids, mixtures, and batch operation, lid 1 is opened and the mixedwaste and/or transuranic/actinides (which can be in liquid, solid, and amixture) is placed 83 in the basket 3, whereupon the solid portion ofthe mixed waste and/or transuranic/actinides is retained and the liquidportion flows through the basket and into the anolyte. The locking latch76 is activated.

The pumps 19 and 43 begin circulation 85 of the anolyte 87 and catholyte89, respectively. As soon as the electrolyte circulation is establishedthroughout the system, the mixers 7 and 35 begin to operate 91 and 93.Depending upon mixed waste characteristics (e.g., reaction kinetics,heat of reaction, etc.) it may be desirable to introduce the mixed wasteand/or transuranic/actinides into a room temperature or cooler anolytesystem with little or none of the mediator redox couple in the oxidizedform. Once flow is established the thermal controls units 21, 22, 45,and 46 are turned on 95/97, initiating predetermined anodic oxidationand electrolyte heating programs.

The electrochemical cell 25 is energized 94 (by electrochemical cellcommands 56) to apply the correct voltage and current as is monitored bythe voltmeter 57 and ammeter 55 determined by the controller program. Byusing programmed electrical power levels and electrolyte temperature itis possible to maintain a predetermined mixed waste destruction and/orthe dissolution of transuranic/actinides rate profile such as arelatively constant reaction rate as the more reactive mixed wasteand/or transuranic/actinides components are oxidized, thus resulting inthe remaining mixed waste and/or transuranic/actinides becoming less andless reactive, thereby requiring more and more vigorous oxidizingconditions.

The ultrasonic sources 9 and 48 and ultraviolet systems 11 are activated99 and 101 in the anolyte reaction chambers 5 b and catholyte reactionchamber 31 respectively, if those options are chosen in the controllerprogram.

The CO₂ vent 14 is activated 103 to release CO₂ from the mixed wasteand/or transuranic/actinides oxidation process in the anolyte reactionchambers 5 b. Air sparge 37 draws air 105 into the catholyte reservoir31, and the air is discharged out the atmospheric vent 47. The progressof the destruction process may be monitored in the controller (oxidationsensor 67) by various cell voltages and currents 55, 57 (e.g., opencircuit, anode vs. reference electrode, ion specific electrodes, etc,)as well as monitoring anolyte off-gas (using the sensor 65) compositionfor CO₂, CO and oxygen content.

When the oxidation sensors 65 and 67 determine the desired degree ofmixed waste destruction and/or the dissolution of transuranic/actinideshas been obtained 107, the system goes to standby 109. The systemoperator executes system shutdown 111 using the controller keyboard 53.

EXAMPLES

The following examples illustrate the application of the process and theapparatus.

Example (1) Destruction of Mixed Waste Surrogates

The following surrogates have been destroyed in the MEO SystemApparatus: tungsten carbide, manganese dioxide, etc. The destructionresults were the oxidizing of the surrogates into solution.

Example (2) Efficient and Environmentally Safe Products

The MEO process produces oxidized the mixed waste into CO₂, water, andtrace inorganic salts all of which are considered benign forintroduction into the environment by regulatory agencies. Thetransuranic/actinides ions produced by the MEO process are removed fromthe anolyte solution by either a precipitation or filtering process. Thecost of using the MEO process in this invention is competitive with boththe existing methodologies (silver II, cobalt III, cerium IV andperoxysulfate). The MEO process is uniquely suited for destruction ofmixed waste because water is actually a source of secondary oxidizingspecies, rather than parasitic reactions competing for the mediatoroxidizing species. Furthermore, the energy that must be provided in theMEO process to heat the waste stream water component from ambient to theelectrolyte operating temperature (i.e., 80° C. maximum temperatureincrease) is trivial compared to the water enthalpy increase required inincineration based processes.

Example (3) System Flexibility

The system is built so that the composition of the electrolyte may bechanged to adapt the system to a given composition of the mixed wasteand/or transuranic/actinides stream. Different composition of mixedwaste and/or transuranic/actinides stream can be processed by the samesystem by either using the same electrolyte or replacing the mediatorand electrolyte (either or both the catholyte and anolyte) more suitablefor the alternative mixed waste and/or transuranic/actinides. The systemis configured with ports to flush and drain the anolyte and catholyteseparately.

Example (4) System By-Products are Safe

The system flexibility provides for the introduction of more then onemediator ion resulting in marked improvement in the efficiency of theelectrolyte. Furthermore, the wide choice of mediators listed in Table Ior available as POMs,-and electrolytes in this patent, desensitizes thesystem to the formation of participates in solution (i.e. allowsincreased ease in preventing formation of unstable oxy compounds).

While the invention has been described with reference to specificembodiments, modifications and variations of the invention may beconstructed without departing from the scope of the invention, which isdefined in the following characteristics and features.

The invention provides the following new characteristics and features:

1. A process for treating and oxidizing mixed waste and/ortranuranics/actinides materials comprising disposing an electrolyte inan electrochemical cell, separating the electrolyte into an anolyteportion and a-catholyte portion with an ion-selective membrane or semipermeable membrane applying a direct current voltage between the anolyteportion and the catholyte portion, placing the mixed Waste and/ortransuranic/actinides materials in the anolyte portion, and oxidizingthe mixed waste and/or transuranic/actinides materials in the anolyteportion with a mediated electrochemical oxidation (MEO) process, whereinthe anolyte portion further comprises a mediator in aqueous solution andthe electrolyte is an acid, neutral or alkaline aqueous solution.

2. The process of paragraph 1, wherein:

a. the anolyte portion further comprises one or more simple anionsmediator ions species selected from the group described in Table I inthe aqueous solution and the electrolyte is an acid, neutral or alkalinesolution;

b. The oxidizing species are selected from one or more Type Iisopolyanions (i.e., complex anion redox couple mediators) containingtungsten, molybdenum, vanadium, niobium, tantalum, or combinationsthereof as addenda atoms in aqueous solution and the electrolyte is anacid, neutral or alkaline aqueous solution;

c. The oxidizing species are selected from one or more Type Iheteropolyanions formed by incorporation into the aforementionedisopolyanions, as heteroatoms, any of the elements listed in Table II,either singly or in combination thereof in the aqueous solutions and theelectrolyte is an acid, neutral, or alkaline aqueous solution;

d. The oxidizing species are selected from one or more of anyheteropolyanions containing at least one heteroatom type (i.e., element)contained in both Table I and Table II-in the aqueous solutions and theelectrolyte is an acid, neutral, or alkaline aqueous solution;

e. The oxidizing species are selected from combinations of anion redoxcouple mediators from any or all of the previous four subparagraphs (2a., 2 b., 2 c., and 2 d.);

f. introducing catalyst additives to the electrolyte and contributing tokinetics of the mediated electrochemical processes while keeping theadditives from becoming directly involved in the oxidizing of the mixedwaste and/or transuranic/actinides materials;

g. adding stabilizing compounds to the electrolyte and stabilizinghigher oxidation state species of the simple and complex anion redoxcouple mediators;

h. each of the species has normal valence states and higher valenceoxidizing states and further comprising creating the higher valenceoxidizing states of the oxidizing species by stripping electrons fromnormal valence state species in the electrochemical cell;

i. the oxidizing species are “super oxidizers” (SO) (typically exhibitoxidation potentials at least equal to that of the Ce⁺³/Ce⁺⁴ redoxcouple (i.e., 1.7 volts at 1 molar, 25° C. and pH 1)) which are redoxcouple species that have the capability of producing free radicals suchas hydroxyl or perhydroxyl and further comprising creating secondaryoxidizers by reacting the SO's with water;

j. using an alkaline solution for aiding decomposing of the mixed wasteand/or transuranic/actinides materials derived from the saponification(i.e., base promoted ester hydrolysis) of fatty acids to form watersoluble alkali metal salts of the fatty acids (i.e., soaps) andglycerin, a process similar to the production of soap from animal fat byintroducing it into a hot aqueous lye solution;

k. using an alkaline anolyte solution that absorbs CO₂ forming fromoxidation of the mixed waste sodium bicarbonate/carbonate solution whichsubsequently circulates through the electrochemical cell, producing apercarbonate oxidizer;

l. super oxidizers generating inorganic free radicals in aqueoussolutions from species such as but not limited to carbonate, azide,nitrite, nitrate, phosphite, phosphate, sulfite, sulfate, selenite,thiocyanate, chloride, bromide, iodide, and formate oxidizing species;

m. regenerating the anolyte portion within the electrochemical cell;

n. the membrane(separator between anolyte and catholyte solutions) canbe microporous plastic, sintered glass frit, etc.;

o. the impression of an AC voltage upon the DC voltage to retard theformation of cell performance limiting surface films on the electrodeand/or membranes;

p. disposing a foraminous basket in the anolyte;

q. adding oxygen (this is necessary only for HNO₃ ⁻ or NO₃ ⁻ salts) tothe catholyte portion;

r. described in Table I (simple anions); Type I isopolyanions containingtungsten, molybdenum, vanadium, niobium, tantalum, or combinationsthereof as addenda atoms; Type I heteropolyanions formed byincorporation into the aforementioned isoopolyanions, as heteroatoms,any of the elements listed in Table II, either singly or in combinationsthereof; or any heteropolyanions containing at least one heteroatom type(i.e., element) contained in both Table I and Table II;

s. adjust the temperature (e.g. between 0° C. and slightly below theboiling point) of the anolyte before it enters the electrochemical cellto enhance the generation of the oxidized form of the anion redox couplemediator; and

t. adjust the temperature between 0° C. and slightly below the boilingpoint of the anolyte entering the anolyte reaction chamber to affect thedesired chemical reactions at the desired rates following the loweringof the temperature of the anolyte entering the electrochemical cell.

3. The process of paragraph 1, wherein:

a. introducing ultraviolet energy into the anolyte portion anddecomposing hydrogen peroxide into hydroxyl free radicals therein,thereby increasing efficiency of the MEO process by converting productsof electron consuming parasitic reactions (i.e., ozone and hydrogenperoxide) into viable free radical (i.e., secondary) oxidizers withoutthe consumption of additional electrons;

b. using a surfactant to be added to the anolyte promote dispersion ofthe mixed waste or intermediate stage reaction products within theaqueous solution when these mixed waste or reaction products are notwater-soluble and tend to form immiscible layers;

c. using simple and/or complex redox couple mediators, and attackingspecific halogenated hydrocarbon molecules with the oxidizing specieswhile operating at low temperatures thus preventing the formation ofdioxins and furans;

c. breaking down mixed waste materials into organic compounds andattacking the organic compounds using either the simple and/or complexanion redox couple mediator or inorganic free radicals to generatingorganic free radicals;

e. raising normal valence state anions to a higher valence state andstripping the normal valence state anions of electrons in theelectrochemical cell; [The oxidized forms of any other redox couplespresent are produced either by similar anodic oxidation or reaction withthe oxidized form of other redox couples present. The oxidized speciesof the redox couples oxidize the mixed waste and/ortransuranic/actinides molecules and are themselves converted to theirreduced form, whereupon they are reoxidized by either of theaforementioned mechanisms and the redox cycle continues];

f. circulating anions through an electrochemical cell to affect theanodic oxidation of the reduced form of the reversible redox couple intothe oxidized form;

g. contacting anions with mixed waste and/or transuranic/actinidesmaterials in the anolyte portion;

h. circulating anions through the electrochemical cell;

i. involving anions with an oxidation potential above a threshold valueof 1.7 volts at 25° C. and pH 1 (i.e., super oxidizer) in a secondaryoxidation process and producing oxidizers;

j. adding a ultra-violet (UV) energy source to the anolyte portion andaugmenting secondary oxidation processes, breaking down hydrogenperoxide into hydroxyl free radicals, and thus increasing the oxidationprocesses; and

k. The oxidizer species addressed in this patent are described in TableI (simple anions redox couple mediators): Type I IPAs formed by Mo, W,V, Nb, Ta, or mixtures there of; Type I HPAs formed by incorporationinto the aforementioned IPAs if any of the elements listed in Table II(heteroatoms) either singly or in thereof; Or any HPA containing atleast one heteroatom type (i.e., element) contained in both Table I andTable II or combinations mediator species from any or all of thesegeneric groups.

4. The process of paragraph 1, further comprising:

a. using oxidizer species that are found in situ in the, mixed waste tobe destroyed, by circulating the mixed waste-anolyte mixture through anelectrochemical cell where the oxidized form of the in situ reversibleredox couple formed by anodic oxidation or alternately reacting with theoxidized form of a more powerful redox couple, if added to the anolyteand anodically oxidized in the electrochemical cell, thereby destroyingthe mixed waste and/or the dissolution of the transuranic/actinidesmaterial;

b. using an alkaline electrolyte, such as but not limited to NaOH or KOHwith mediator species wherein the reduced form of said mediator redoxcouple displays sufficient solubility in said electrolyte to allow thedesired oxidation of the mixed waste to proceed at a practical rate. Theoxidation potential of redox reactions producing hydrogen ions (i.e.,both mediator species and mixed waste molecules reactions) are inverselyproportional to the electrolyte pH, thus with the proper selection of amediator redox couple, it is possible, by increasing the electrolyte pH,to minimize the electric potential required to affect the desiredoxidation process, thereby reducing the electric power consumed per unitmass of mixed waste destroyed and/or the dissolution of thetransuranic/actinides; c. the aqueous solution is chosen from acids suchas but not limited to nitric acid, sulfuric acid, or phosphoric acid, ormixtures thereof; or alkalines such as but not limited to of sodiumhydroxide or potassium hydroxide, or mixtures thereof, or neutralelectrolytes,. such as but not limited to sodium or potassium nitrates,sulfates, or phosphates or mixtures thereof; and d. the use ofultrasonic energy induce microscopic bubble implosion which may be usedto affect a desired reduction in size of the individual second phasewaste volumes dispersed in the anolyte.

5. The process of paragraph 1, further comprising:

a. interchanging oxidizing species in a preferred embodiment withoutchanging equipment; and

b. the electrolyte is acid, neutral, or alkaline in aqueous solution.

6. The process of paragraph 1, further comprising:

a. separating the anolyte portion and the catholyte portion with anion-selective or semi permeable membrane or microporous polymer, porousceramic or glass frit membrane;

b. energizing the electrochemical cell at a electrical potentialsufficient to form the oxidized form of the redox couple having thehighest oxidation potential in the anolyte;

c. introducing mixed waste materials into the anolyte portion;

d. forming the reduced form of one or more reversible redox couples bycontacting with oxidizable molecules, the reaction with which oxidizesthe oxidizable material with the concuminent reduction of the oxidizedform of the reversible redox couples to their reduced form;

e. a ultrasonic source connected to the anolyte for augmenting secondaryoxidation processes by momentarily heating the hydrogen peroxide in theelectrolyte to 4800° C. at 1000 atmospheres thereby dissociating thehydrogen peroxide into hydroxyl free radicals thus increasing theoxidation processes;

f. oxidation potentials of redox reactions producing hydrogen ions areinversely related to pH;

g. the process is performed at a temperature from slightly above 0° C.to slightly below the boiling point of the electrolyte usually less then100° C.;

h. the temperature at which the process is performed is varied;

i. the treating and oxidizing mixed waste and/or transuranic/actinidescomprises treating and oxidizing solid waste and/ortransuranic/actinides;

j. the treating and oxidizing mixed waste and/or transuranic/actinidescomprises treating and oxidizing liquid waste and/ortransuranic/actinides;

k. the treating and oxidizing mixed waste and/or transuranic/actinidescomprises treating and oxidizing a combination of liquids and solids;and

l. removing and treating precipitates resulting from combinations ofoxidizing species and other species released from the mixed waste duringdestruction.

7. The process of paragraph 1, further comprising that it is notnecessary for both the anolyte and catholyte solutions to contain thesame electrolyte rather each electrolyte system may be independent ofthe other, consisting of an aqueous solution of acids, typically but notlimited to nitric, sulfuric or phosphoric; alkali, typically but notlimited to sodium or potassium hydroxide; or neutral salt, typically butnot limited to sodium or potassium salts of the afore mentioned strongacids.

8. The process of paragraph 1, further comprising the operating of theelectrochemical cell at a current density greater then 0.5 amp persquare centimeter across the membrane, even though this is the limitover which there is the possibility that metallic anions may leakthrough the membrane in small quantities, and recovering the metallicanions through a devise such as a resin column thus allowing a greaterrate of destruction of materials in the anolyte chamber.

9. The process of paragraph 1, wherein:

a. the catholyte solution further comprises an aqueous solution and theelectrolyte in the solution is composed of acids, typically but notlimited to nitric, sulfuric or phosphoric; or alkali, typically but notlimited to sodium or potassium hydroxide; or neutral salt, typically butnot limited to sodium or potassium salts of the afore mentioned strongacids;

b. adding oxygen (this is necessary only for HNO₃ ⁻ or NO₃ ⁻ salts) tothe catholyte portion;

c. concentration of electrolyte in the catholyte is governed by itseffect upon the conductivity of the catholyte solution desired in theelectrochemical cell;

d. ultrasonic energy induced microscopic bubble implosion is used toaffect vigorous mixing in the catholyte solution where it is desirableto oxidize nitric acid and the small amounts of nitrogen oxides whennitric acid is used in the catholyte electrolyte;

e. mechanical mixing is used to affect vigorous mixing in the catholytesolution where it is desirable to oxidize nitric acid and the smallamounts of nitrogen oxides;

f. air is introduced into the catholyte solution to promote oxidation ofnitric acid and the small amounts of nitrogen oxides when nitric acid isused in the catholyte electrolyte;

g. air is introduced into the catholyte solution to dilute any hydrogenproduced in the catholyte solution before being released; and

h. hydrogen gas evolving from the cathode is feed to an apparatus thatuses hydrogen as a fuel such as a proton exchange membrane (PEM)fuelcell.

10. An apparatus for treating and oxidizing mixed waste and/ortransuranic/actinides materials comprising an electrochemical cell, anelectrolyte disposed in the electrochemical cell, an ion-selective orsemi permeable membrane, disposed in the electrochemical cell forseparating the cell into anolyte and catholyte chambers and separatingthe electrolyte into anolyte and catholyte portions, electrodes furthercomprising an anode and a cathode disposed in the electrochemical cellrespectively in the anolyte and catholyte chambers and in the anolyteand catholyte portions of the electrolyte, a power supply connected tothe anode and the cathode for applying a direct current voltage betweenthe anolyte and the catholyte portions of the electrolyte, and oxidizingof the mixed waste and/or transuranic/actinides materials in the anolyteportion with a mediated electrochemical oxidation (MEO) process whereinthe anolyte portion further comprises a mediator in aqueous solution andthe electrolyte is an acid, neutral or alkaline aqueous solution.

11. The apparatus of paragraph 10, wherein:

a. adding stabilizing compounds to the electrolyte such as tellurate orperiodate ions which serve to overcome and stabilize the short lifetimeof the oxidized form of the higher oxidation state species of the simpleand complex anion redox couple mediators;

b. the oxidizer species addressed in this patent are described in TableI (simple anions redox couple mediators);

c. the oxidizer species addressed in this patent are described in TableI (simple anions redox couple mediators): Type I IPAs formed by Mo, W,V, Nb, Ta, or mixtures there of; Type I HPAs formed by incorporationinto the aforementioned IPAs if any of the elements listed in Table II(heteroatoms) either singly or in thereof; Or any HPA containing atleast one heteroatom type (i.e., element) contained in both Table I andTable II;

d. the oxidizer species addressed in this patent are combinationsmediator species from any or all of these generic groups;

e. the oxidizing species are super oxidizers and further comprisingcreating secondary oxidizers by reacting the super oxidizers with theaqueous anolyte;

f. an alkaline solution for aiding decomposing the mixed waste and thedissolution of the actinide materials;

g. an alkaline solution for absorbing CO₂ and forming alkali metalbicarbonate/carbonate for circulating through the electrochemical cellfor producing a percarbonate oxidizer;

h. using oxidizing species from the MEO process inorganic free radicalsmay be generated in aqueous solutions derived from carbonate, azide,nitrite, nitrate, phosphite, phosphate, sulfite, sulfate, selenite,thiocyanate, chloride, bromide, iodide, and species;

i. organic free radicals for aiding the MEO process and breaking downthe mixed waste materials into simpler (i.e., smaller molecularstructure) organic compounds;

j. anions with an oxidation potential above a threshold value of 1.7 at25° C. and pH 1 volts (i.e., super oxidizer) for involving in asecondary oxidation process for producing oxidizers;

k. the use of ultrasonic energy induce microscopic bubble implosionwhich is used to affect a desired reduction in sized of the individualsecond phase mixed waste volumes dispersed in the anolyte;

l. membrane can be microporous polymer, ceramic or glass frit;

m. with the possible impression of an AC voltage upon the DC voltage toretard the formation of cell performance limiting surface films on theelectrode and/or membranes; and

n. external air is introduced through an air sparge into the catholytereservoir where oxygen contained in the air oxidizes nitrogen compoundsproduced by the cathode reactions (this is necessary only when nitrogencompounds can occur in the catholyte).

12. The apparatus of paragraph 10, wherein:

a. each of the oxidizing species has normal valence states (i.e.,reduced form of redox couple) and higher valence oxidizing states andfurther comprising creating the higher valence oxidizing states (i.e.,oxidized form of redox couple) of the oxidizing species by stripping andreducing electrons off normal valence state species in theelectrochemical cell;

b. using species that are usable in alkaline solutions since oxidationpotentials of redox reactions producing hydrogen ions are inverselyrelated to pH which reduces the electrical power required to destroy themixed waste;

c. further oxidizing species, and attacking specific halogenatedhydrocarbon molecules with the oxidizing species while operating attemperatures sufficiently low so as to preventing the formation of toxicmaterials (such as dioxins and furans);

d. energizing the electrochemical cell at a potential level sufficientto form the oxidized form of the redox couple having the highestoxidation potential in the anolyte;

e. adjust the temperature (e.g. between 0° C. and slightly below theboiling point) of the anolyte with the heat exchanger before it entersthe electrochemical cell to enhance the generation of the oxidized formof the anion redox couple mediator; and

f. raise the temperature between 0° C. and slightly below the boilingpoint of the anolyte entering the anolyte reaction chamber with the heatexchanger to affect the desired chemical reactions at the desired ratesfollowing the lowering of the temperature of the anolyte entering theelectrochemical cell.

13. The apparatus of paragraph 10, wherein:

a. the oxidizing species are one or more Type I isopolyanions (i.e.,complex anion redox couple mediators) containing tungsten, molybdenum,vanadium, niobium, tantalum, or combinations thereof as addenda atoms inaqueous solution and the electrolyte is an acid, neutral or alkalineaqueous solution;

b. the oxidizing species are one or more Type I heteropolyanions formedby incorporation into the aforementioned isopolyanions, as heteroatoms,any of the elements listed in Table II, either singly or in combinationthereof in the aqueous solutions and the electrolyte is an acid,neutral, or alkaline aqueous solution;

c. the oxidizing species are one or more of any heteropolyanionscontaining at least one heteroatom type (i.e., element) contained inboth Table I and Table II in the aqueous solutions and the electrolyteis an acid, neutral, or alkaline aqueous solution;

d. the oxidizing species are combinations of anion redox couplemediators from any or all of the previous four subparagraphs (13 a., 13b., 13 c);

e. the oxidizing species are higher valence state of species found insitu for destroying the mixed waste and/or the dissolution of actinidematerial; and

f. the electrolyte is an acid, neutral, or alkaline aqueous solution.

14. The apparatus of paragraph 10, further comprising:

a. the aqueous solution is chosen from acids such as but not limited tonitric acid, sulfuric acid, or phosphoric acid; alkalines such as butnot limited to of sodium hydroxide or potassium hydroxide; or neutralelectrolytes such as but not limited to sodium or potassium nitrates,sulfates, or phosphates;

b. a with a ion-selective or semi-permeable, microporous polymer,ceramic or sintered glass frit membrane for separating the anolyteportion and the catholyte portion while allowing hydrogen or hydroniumion passage from the anolyte to the catholyte;

c. oxidation potentials of redox reactions producing hydrogen ions areinversely related to pH;

d. the mixed waste and/or transuranic/actinides is liquid waste;

e. the mixed waste and/or transuranic/actinides is solid waste;

f. the mixed waste and/or transuranic/actinides is a combination ofliquids and solids and non-organic waste; and

g. oxidizing species may be interchanged in a preferred embodimentwithout changing equipment.

15. The apparatus of paragraph 10, further comprising:

a. anolyte reaction chamber(s) 5(b,c) and buffer tank 20 housing thebulk of the anolyte portion and the foraminous basket 3;

b. anolyte reaction chamber 5 a housing the bulk of the anolyte portion;

c. an anolyte reaction chamber 5 d and buffer tank 20 housing the bulkof the anolyte portion;

d. an input pump 10 is attached to the anolyte reaction chamber 5 a toenter liquid mixed waste and/or transuranic/actinides into the anolytereaction chamber 5 a;

e. a spray head 4(a) and a stream head 4(b) attached to the tubingcoming from the electrochemical cell 25 that inputs the anolytecontaining the oxidizer into the anolyte reaction chamber(s) 5(a,b,c)and buffer tank 20 in such a manner as to promote mixing of the incominganolyte with the anolyte already in the anolyte reaction chambers(s)5(a,b,c);

f. a anolyte reaction chamber(s) 5(b,c) houses a foraminous basket 3with a top that holds solid forms of the mixed waste and/ortransuranic/actinides in the electrolyte;

g. a hinged lid 1 attached to the reaction chamber(s) 5(a,b,c) allowinginsertion of mixed waste and/or transuranic/actinides into the anolyteportion as liquid, solid, or a mixture of liquids and solids;

h. the lid 1 contains an locking latch 76 to secure the anolyte reactionchamber(s) 5(a,b,c) during operation;

i. a suction pump 8 is attached to buffer tank 20 to pump anolyte to theanolyte reaction chamber(s) 5(c,d);

j. an input pump 10 is attached to buffer tank 20 to pump anolyte fromthe anolyte reaction chamber(s) 5(c,d) back to the buffer tank 20; and

k. an air pump 32 is attached to buffer tank 20 to pump off gases fromthe anolyte reaction chamber(s) 5(c,d) back to the buffer tank 20 forfurther oxidation.

16. The apparatus of paragraph 10, further comprising:

a. an ultraviolet source 11 connected to the anolyte reaction chamber(s)5(a,b,c) and buffer tank 20 and decomposing hydrogen peroxide intohydroxyl free radicals therein and increasing efficiency of the MEOprocess by recovering energy through the oxidation of the mixed wasteand/or transuranic/actinides materials in the anolyte chamber by thesesecondary oxidizers;

b. an ultrasonic source 9 connected to the anolyte reaction chamber(s)5(a,b,c) and buffer tank 20 for augmenting secondary oxidation processesby heating the hydrogen peroxide containing electrolyte to produceextremely short lived and localized conditions of 4800° C. and 1000atmospheres pressure within the anolyte to dissociate hydrogen peroxideinto hydroxyl free radicals thus increasing the oxidation processes;

c. an ultrasonic energy 9 source connected into the anolyte reactionchamber(s) 5(a,b,c) and buffer tank 20 for irradiating cell membranes inmixed waste materials by momentarily raising temperature within the cellmembranes and causing cell membrane fail and rupture thus creatinggreater exposure of cell contents to oxidizing species in the anolyte;

d. the use of ultrasonic energy for mixing material in the anolyte, viathe ultrasonic energy source 9, to induce microscopic bubble implosionwhich is used to affect a desired reduction in size of the individualsecond phase waste volumes and disperse throughout the anolyte;

e. a mixer 35 for stirring the anolyte connected to the anolyte reactionchamber(s) 5(a,b,c) and the buffer tank 20;

f. a CO₂ vent 14 for releasing CO₂ atmospherically;

g. an external CO₂ vent 14 connected to the housing for releasing CO₂into the atmosphere;

h. a penetrator 34 is attached to the basket 3 to puncture the solidsthus increasing the surface area exposed to the oxidizer;

i. an inorganic compounds removal and treatment system 15 connected tothe anolyte pump is used should there be more than trace amount ofchlorine, or other precipitate forming anions present in the mixed wastebeing processed, thereby precluding formation of unstable oxycompounds(e.g., perchlorates, etc.);

j. an off-gas cleaning system 16 comprises scrubber/absorption columns;

k. a condenser 13 connected to the anolyte reaction chamber(s) 5(a,b,c)and buffer tank 20;

l. non-condensable incomplete oxidation products (e.g., low molecularweight organics, carbon monoxide, etc.) are reduced to acceptable levelsfor atmospheric release by a gas cleaning system 16;

m. gas-cleaning system 16 is not a necessary component of the MEOapparatus for the destruction of most types of mixed waste;

n. if the gas cleaning system 16 is incorporated into the MEO apparatus,the anolyte off-gas is contacted in a gas cleaning system 16 wherein thenoncondensibles from the condenser 13 are introduced into the lowerportion of the gas cleaning system 16 through a flow distribution systemand a small side stream of freshly oxidized anolyte direct from theelectrochemical cell 25 is introduced into the upper portion of thecolumn, this results in the gas phase continuously reacting with theoxidizing mediator species as it rises up the column past the downflowing anolyte;

o. external drain 12, for draining to the organic compound removalsystem 17 and the inorganic compounds removal and treatment system 15,and for draining the anolyte system;

p. organic compounds recovery system 17 is used to recover a) organicmaterials that are benign and do not need further treatment, and b)organic materials (such as biphenyls) that may be used in the form theyhave been reduced and thus would be recovered for that purpose;

q. optional inorganic compound removal and treatment systems 15 is usedshould there be more than trace amount of precipitate forming ionspresent in the mixed waste being processed, thereby precluding formationof unstable oxycompounds (e.g., perchlorates, etc.);

r. small thermal control units 21 and 22 are connected to the flowstream to heat or cool the anolyte to the selected temperature range;

s. anolyte is circulated into the reaction chambers 5(a,b,c,d) throughthe electrochemical cell 25 by pump 19 on the anode 26 side of themembrane 27;

t. a flush(s) 18 for flushing the anolyte and catholyte system;

u. filter 6 is located at the base of the reaction chambers 5(a,b,c,d)and buffer tank 20 to limit the size of the solid particles toapproximately 1 mm in diameter;

v. membrane 27 in the electrochemical cell 25 separates the anolyteportion and catholyte portion of the electrolyte;

w. electrochemical cell 25 is energized by a DC power supply 29, whichis powered by the AC power supply 30;

x. DC power supply 29 is low voltage high current supply usuallyoperating below 4V DC but not limited to that range;

y. AC power supply 29 operates off a typical 110v AC line for thesmaller units and 240v AC for the larger units;

z. electrolyte containment boundary is composed of materials resistantto the oxidizing electrolyte (e.g., stainless steel, PTFE, PTFE linedtubing, glass, etc.); and

aa. an electrochemical cell 25 connected to the anolyte reactionchamber(s) 5(a,b,c) and buffer tank 20.

17. The apparatus of paragraph 10, wherein:

a. in the chambers 5(a,b,c) and buffer tank 20 is the aqueous acid,alkali, or neutral salt electrolyte and mediated oxidizer speciessolution in which the oxidizer form of the mediator redox coupleinitially may be present or may be generated electrochemically afterintroduction of the mixed waste and/or transuranic/actinides andapplication of DC power 30 to the electrochemical cell 25;

b. mixed waste and/or transuranic/actinides is introduced when theanolyte is at room temperature, operating temperature or some optimumintermediate temperature;

c. DC power supply 30 provides direct current to an electrochemical cell25;

d. pump 19 circulates the anolyte portion of the electrolyte and themixed waste and/or transuranic/actinides material is rapidly oxidized attemperatures below 100° C. and ambient pressure;

e. in-line filter 6 prevents solid particles large enough to clog theelectrochemical cell 25 flow paths from exiting this reaction chambers5(a,b,c,d) and buffer tank 20;

f. residue is pacified in the form of a salt and may be periodicallyremoved through the Inorganic Compound Removal and Treatment System 15and drain outlets 12;

g. electrolyte may be changed through this same plumbing forintroduction into the reaction chambers 5 and 31;

h. catholyte reservoir 31 has a screwed top 33 (shown in FIG. 1), whichallow access to the catholyte reservoir 31 for cleaning and maintenanceby service personnel;

i. the system is scalable to a unit large for a large industrialapplication;

j. the process operates at low temperature and ambient atmosphericpressure and does not generate toxic compounds during the destruction ofthe mixed waste and/or transuranic/actinides, making the process indoorscompatible;

k. the system is scalable to a unit large for a large industrialapplication; and

l. CO₂ oxidation product from the anolyte system A is vented out the CO₂vent 14.

18. The apparatus of paragraph 10, wherein:

a. an anolyte recovery system 41 connected to the catholyte pump (43);

b. a thermal control unit 45 connected to the catholyte reservoir 31 forvarying the temperature of the catholyte portion;

c. a catholyte reservoir 31 connected to the cathode portion of theelectrochemical cell;

d. bulk of the catholyte is resident in the catholyte reservoir 31;

e. catholyte portion of the electrolyte flows into a catholyte reservoir31;

f. an air sparge 37 connected to the catholyte reservoir 31 forintroducing air into the catholyte reservoir;

g. an anolyte recovery system 41 for capturing the anions and forreintroducing the anions into the anolyte reaction chamber or disposalfrom the catholyte electrolyte;

h. an off-gas cleaning system 39 for cleaning gases before release intothe atmosphere connected to the catholyte reservoir 31;

i. an atmospheric vent 47 for releasing gases into the atmosphereconnected to the off-gas cleaning system;

j. cleaned gas from the off-gas cleaning system 39 is combined withunreacted components of the air introduced into the system anddischarged through the atmospheric vent 47;

k. a catholyte reservoir 31 has a screwed top 33 (shown in FIG. 1A),which allow access to the reservoir 31 for cleaning and maintenance byservice personnel;

l. a mixer 35 for stirring the catholyte connected to the catholytereservoir 31;

m. a catholyte pump 43 for circulating catholyte back to theelectrochemical cell connected to the catholyte reservoir;

n. a drain 12 for draining catholyte;

o. a flush 18 for flushing the catholyte system;

p. an air sparge 37 connected to the housing for introducing air intothe catholyte reaction chamber 31;

q. catholyte portion of the electrolyte is circulated by pump 43 throughthe electrochemical cell 25 on the cathode 28 side of the membrane 27;

r. small thermal control units 45 and 46 are connected to the catholyteflow stream to heat or cool the catholyte to the selected temperaturerange;

s. contact of the oxidizing gas with the catholyte may be enhanced byusing conventional techniques for promoting gas/liquid contact byultrasonic vibration 48, mechanical mixing 35, etc.;

t. operating the electrochemical cell 25 at higher than normal membrane27 current densities (i.e., above about 0.5 amps/cm²) increases the rateof mixed waste destruction and/or the dissolution of thetransuranic/actinides, but also result in increased mediator iontransport through the membrane into the catholyte;

u. optional anolyte recovery system 41 is positioned on the catholyteside;

v. systems using non-nitric acid catholytes may also require airsparging to dilute and remove off-gas such as hydrogen;

w. some mediator oxidizer ions may cross the membrane 27 and this optionis available if it is necessary to remove them through the anolyterecovery system 41 to maintain process efficiency or cell operability,or their economic worth necessitates their recovery;

x. using the anolyte recovery system 41 the capitol cost of expandingthe size of the electrochemical cell 25 can be avoided; and

y. operating the electrochemical cell 25 at higher than normal membranecurrent density (i.e., above about 0.5 amps per centimeter squared)improves economic-efficiency.

19. The apparatus of paragraph 10, wherein:

a. operator runs the MEO Apparatus (FIG. 1A) and FIG. 1B by using theMEO Controller depicted in FIG. 3 MEO System Model 5.b Controller;

b. controller 49 with microprocessor is connected to a monitor 51 and akeyboard 53;

c. operator inputs commands to the controller 49 through the keyboard 53responding to the information displayed on the monitor 51;

d. controller 49 runs a program that sequences the steps for theoperation of the MEO apparatus;

e. program has pre-programmed sequences of standard operations that theoperator may follow or choose his own sequences of operations;

f. controller 49 allows the operator to select his own sequences withinlimits that assure a safe and reliable operation;

g. controller 49 sends digital commands that regulates the electricalpower (AC 30 and DC 29) to the various components in the MEO apparatus:pumps 19 and 43, mixers 7 and 35, thermal controls 21, 22, 45, 46, heatexchangers 23 and 24, ultraviolet sources 11, ultrasonic sources 9 and48, CO₂ vent 14, air sparge 37, and electrochemical cell 25;

h. controller receives component response and status from thecomponents;

i. controller sends digital commands to the sensors to access sensorinformation through sensor responses;

j. sensors in the MEO apparatus provide digital information on the stateof the various components;

k. sensors measure flow rate 59, temperature 61, pH 63, CO₂ venting 65,degree of oxidation 67, air sparge sensor 69, etc; and

l. controller 49 receives status information on the electrical potential(voltmeter 57) across the electrochemical cell or individual cells if amulti-cell configuration and between the anode(s) and referenceelectrodes internal to the cell(s) 25 and the current (ammeter 55)flowing between the electrodes within each cell.

20. The apparatus of paragraph 10, wherein:

a. preferred embodiment, MEO System Model 5.b is sized for use for asmall to mid-size application for the destruction of solids and mixturesof solids and liquid mixed waste and/or transuranic/actinides beingbatch feed. This embodiment depicts a configuration using the systemapparatus presented in FIGS. 1A and 1C. Other preferred embodiments(representing FIGS. 1B, 1D, and 1E) have differences in the externalconfiguration and size but are essentially the same in internal functionand components as depicted in FIGS. 1A and 1B;

b. preferred embodiment in FIG. 2 comprises a housing 72 constructed ofmetal or high strength plastic surrounding the electrochemical cell 25,the electrolyte and the foraminous basket 3;

c. AC power is provided to the AC power supply 30 by the power cord 78;

d. monitor screen 51 is incorporated into the housing 72 for displayinginformation about the system and about the mixed waste and/ortransuranic/actinides being treated;

e. control keyboard 53 is incorporated into the housing 72 for inputtinginformation into the system;

f. monitor screen 51 and the control keyboard 53 may be attached to thesystem without incorporating them into the housing 72;

g. system model 5.b has a control keyboard 53 for input of commands anddata;

h. monitor screen 51 to display the systems operation and functions;

i. status lights 73 for on, off and standby, are located below thekeyboard 53 and monitor screen 51;

j. in a preferred embodiment, status lights 73 are incorporated into thehousing 72 for displaying information about the status of the treatmentof the mixed waste and/or transuranic/actinides material;

k. air sparge 37 is incorporated into the housing 72 to allow air to beintroduced into the catholyte reservoir 31 below the surface of thecatholyte;

l. a CO₂ vent 14 is incorporated into the housing 72 to allow for CO₂release from the anolyte reaction chamber housed within;

m. in a preferred embodiment, the housing includes means for cleaningout the MEO mixed waste and/or transuranic/actinides treatment system,including a flush(s) 18 and drain(s) 12 through which the anolyte andcatholyte pass;

n. the preferred embodiment further comprises an atmospheric vent 47facilitating the releases of gases into the atmosphere from thecatholyte reservoir 31;

o. hinged lid 1 is opened and the mixed waste and/ortransuranic/actinides is deposited in the basket 3 in the anolytereaction chamber 5 b;

p. lid stop 2 keeps lid opening controlled; and

q. hinged lid 1 is equipped with a locking latch 76 that is operated bythe controller 49.

21. The apparatus of paragraph 10, wherein:

a. MEO apparatus is contained in the housing 72;

b. MEO system is started 81 by the operator engaging the ‘ON’ button(status buttons 73) on the control keyboard 53;

c. system controller 49, which contains a microprocessor, runs theprogram that controls the entire sequence of operations 82;

d. monitor screen 51 displays the steps of the process in the propersequence;

e. status lights 73 on the panel provide the status of the MEO apparatus(e.g. on, off, ready, standby);

f. lid 1 is opened and the mixed waste and/or transuranic/actinides isplaced 83 in the basket 3 as a liquid, solid, or a mixture of liquidsand solids, whereupon the solid portion of the mixed waste and/ortransuranic/actinides is retained and the liquid portion flows throughthe basket 3 and into the anolyte;

g. locking latch 76 is activated after waste and/ortransuranic/actinides is placed in basket;

h. pumps 19 and 43 are activated which begins circulation 85 of theanolyte 87 and catholyte 89, respectively;

i. once the electrolyte circulation is established throughout thesystem, the mixers 7 and 35 begin to operate 91 and 93;

j. depending upon waste and/or transuranic/actinides characteristics(e.g., reaction kinetics, heat of reaction, etc.) it may be desirable tointroduce the mixed waste and/or transuranic/actinides into a roomtemperature or cooler system with little or none of the mediator redoxcouple in the oxidizer form;

k. once flow is established the thermal controls units 21, 22, 45, and46 are turned on 95/97, initiating predetermined anodic oxidation andelectrolyte heating programs;

l. the electrochemical cell 25 is energized 94 (by cell commands 56) tothe electric potential 57 and current 55 density determined by thecontroller program;

m. by using programmed electrical power and electrolyte temperatureramps it is possible to maintain a predetermined mixed waste destructionrate and/or the dissolution of the transuranic/actinides profile such asa relatively constant reaction rate as the more reactive mixed wasteand/or transuranic/actinides components are oxidized, thus resulting inthe remaining waste and/or transuranic/actinides becoming less and lessreactive, thereby requiring more and more vigorous oxidizing conditions;

n. the ultrasonic 9 and 48 and ultraviolet systems 11 are activated 99and 101 in the anolyte reaction chambers 5(a,b,c) and catholytereservoir 31 if those options are chosen in the controller program;

o. CO₂ vent 14 is activated 103 to release CO₂ from the mixed wasteand/or transuranic/actinides oxidation process in the anolyte reactionchambers 5(a,b,c,d) and buffer tank 20;

p. air sparge 37 and atmospheric vent 47 are activated 105 in thecatholyte system;

q. progress of the destruction process is monitored in the controller(oxidation sensor 67) by various cell voltages and currents 55, 57(e.g., open circuit, anode vs. reference electrode, ion specificelectrodes, etc,) as well as monitoring CO₂, CO, and O₂ gas 65composition for CO₂, CO and oxygen content;

r. mixed waste is being decomposed into water and CO₂ the latter beingdischarged 103 out of the CO₂ vent 14;

s. air sparge 37 draws air 105 into the catholyte reservoir 31, andexcess air is discharged out the atmospheric vent 47;

t. when the oxidation sensor 67 determine the desired degree of mixedwaste destruction and/or the dissolution of the transuranic/actinideshas been obtained 107, the system goes to standby 109;

u. MEO apparatus as an option may be placed in a standby mode with mixedwaste and/or transuranic/actinides being added as it is generatedthroughout the day and the unit placed in full activation duringnon-business hours; and

v. system operator executes system shutdown 111 using the controllerkeyboard 53. TABLE I SIMPLE ANION REDOX COUPLES MEDIATORS SUB GROUPGROUP ELEMENT VALENCE SPECIES SPECIFIC REDOX COUPLES I A None B Copper(Cu) +2 Cu⁻² (cupric) +2 Species/+3, +4 Species HCuO₂ (bicuprite) +3Species/+4 Species CuO₂ ⁻² (cuprite) +3 Cu⁺³ CuO₂ ⁻ (cuprate) Cu₂O₃(sesquioxide) +4 CuO₂ (peroxide) Silver (Ag) +1 Ag¹ (argentous) +1Species/+2, +3 Species AgO⁻ (argentite) +2 Species/+3 Species +2 Ag⁻²(argentic) AgO (argentic oxide) +3 AgO¹ (argentyl) Ag₂O₃ (sesquioxide)Gold (Au) +1 AU⁺ (aurous) +1 Species/+3, +4 Species +3 Au⁺³ (auric) +3Species/+4 Species AuO⁻ (auryl) H₃AuO₃ ⁻ (auric acid) H₂AuO₃ ⁻(monoauarate) HAuO₃ ⁻² (diaurate) AuO₃ ⁻³ (triaurate) Au₂O₃ (auricoxide) Au(OH)₃ (auric hydroxide) +4 AuO₂ (peroxide) II A Magnesium (Mg)+2 Mg⁺² (magnesic) +2 Species/+4 Species +4 MgO₂ (peroxide) Calcium (Ca)+2 Ca⁺² +2 Specics/+4 Species +4 CaO₂ (peroxide) Strontium +2 Sr⁺² +2Species/+4 Species +4 SrO₂ (peroxide) Barium (Ba) +2 Ba⁺² +2 Species/+4Species +4 BaO₂ (peroxide) II B Zinc (Zn) +2 Zn⁺² (zincic) +2 Species/+4Species ZnOH⁺ (zincyl) HZnO₂ ⁻(bizincate) ZnO₂ ⁻² (zincate) +4 ZnO₂(peroxide) Mercury (Hg) +2 Hg⁺² (mercuric) +2 Species/+4 Species Hg(OH)₂(mercuric hydroxide) HHgO₂ ⁻ (mercurate) +4 HgO₂ (peroxide) III ABoron +3 H₃BO₃ (orthoboric acid) +3 Species/+4.5, +5 Species H₂BO₃ ⁻,HBO₃ ⁻², BO₃ ⁻³ (orthoborates) BO₂ ⁻ (metaborate) H₂B₄O₇ (tetraboricacid) HB₄O₇ ⁻/B₄O₇ ⁻² (tetraborates) B₂O₄ ⁻² (diborate) B₆O₁₀ ⁻²(hexaborate) +4.5 B₂O₅ ⁻ (diborate) +5 BO₃ ⁻/BO₂ ⁻.H₂O (perborate)Thallium (Tl) +1 Tl⁺¹ (thallous) +1 Species/+3 or +3.33 Species +3 Tl⁺³(thallic) +3 Species/+3.33 Species TlO⁺, TlOH⁺², Tl(OH)₂ ⁺ (thallyl)Tl₂O₃ (sesquioxide) Tl(OH)₃ (hydroxide) +3.33 Tl₃O₅ (peroxide) B SeeRare Earths and Actinides IV A Carbon (C) +4 H₂CO₃ (carbonic acid) +4Species/+5, +6 Species HCO₃ ⁻ (bicarbonate) CO₃ ⁻² (carbonate) +5 H₂C₂O₆(perdicarbonic acid) +6 H₂CO₄ (permonocarbonic acid) Germanium (Ge) +4H₂GeO₃ (germanic acid) +4 Species/+6 Species HGeO₃ ⁻ (bigermaniate) GeO₃⁻⁴ (germinate) Ge⁺⁴ (germanic) GeO₄ ⁻⁴ H₂Ge₂O₅ (digermanic acid) H₂Ge₄O₉(tetragermanic acid) H₂Ge₅O₁₁ (pentagermanic acid) HGe₅O₁₁ ⁻(bipentagermanate) +6 Ge₅O₁₁ ⁻² (pentagermanate) Tin (Sn) +4 Sn⁺⁴(stannic) +4 Species/+7 Species HSnO₃ ⁻ (bistannate) SnO₃ ⁻² (stannate)SnO₂ (stannic oxide) Sn(OH)₄ (stannic hydroxide) +7 SnO₄ ⁻ (perstannate)Lead (Pb) +2 Pb⁺² (plumbous) +2, +2.67, +3 Species/+4 Species HPbO₂ ⁻(biplumbite) PbOH⁺ PbO₂ ⁻² (plumbite) PbO (plumbus oxide) +2.67 Pb₃O₄(plumbo-plumbic oxide) +3 Pb₂O₃ (sequioxide) Lead (Pb) +4 Pb⁺⁴ (plumbic)+2, +2.67, +3 Species/+4 Species PbO₃ ⁻² (metaplumbate) HPbO₃ ⁻ (acidmetaplumbate) PbO₄ ⁻⁴ (orthoplumbate) PbO₂ (dioxide) B Titanium +4 TiO⁺²(pertitanyl) +4 Species/+6 Species HTiO₄ ⁻ titanate) TiO₂ (dioxide) +6TiO₂ ⁺² (pertitanyl) HTiO₄ ⁻ (acid pertitanate) TiO₄ ⁻² (pertitanate)TiO₃ (peroxide) Zirconium (Zr) +4 Zr⁺⁴ (zirconic) +4 Species/+5, +6, +7Species ZrO⁺² (zirconyl) HZrO₃ ⁻ (zirconate) +5 Zr₂O₅ (pentoxide) +6ZrO₃(peroxide) +7 Zr₂O₇ (heptoxide) Hafnium (Ht) +4 Hf⁺⁴ (hafnic) +4Species/+6 Species HfO⁺² (hafnyl) +6 HfO₃ (peroxide) V A Nitrogen +5HNO₃ (nitric acid) +5 species/+7 Species NO₃ ⁻ (nitrate) +7 HNO₄(pernitric acid) Phosphorus (P) +5 H₃PO₄ (orthophosphoric acid) +5Species/+6, +7 species H₂PO₄ ⁻ (monoorthophosphate) HPO₄ ⁻²(diorthophosphate) PO₄ ⁻³ (triorthophosphate) HPO₃ (metaphosphoric acid)H₄P₂O₇ (pryophosphoric acid) H₅P₃O₁₀ (triphosphoric acid) H₆P₄O₁₃(tetraphosphoric acid) Phosphorus (P) +6 H₄P₂O₈ (perphosphoric acid) +5Species/+6, +7 Species +7 H₃PO₅ (monoperphosphoric acid) Arsenic (As) +5H₃AsO₄ (ortho-arsenic acid) +5 Species/+7 species H₂AsO₄ ⁻ (monoortho-arsenate) HAsO₄ ⁻² (di-ortho-arsenate) AsO₄ ⁻³(tri-ortho-arsenate) AsO₂ ⁺ (arsenyl) +7 AsO₃ ⁺ (perarsenyl) Bismuth(Bi) +3 Bi⁺³ (bismuthous) +3 Species/+3.5, +4, +5 Species BiOH⁺²(hydroxybismuthous) BiO⁺ (bismuthyl) BiO₂ ⁻ (metabismuthite) +3.5 Bi₄O₇(oxide) +4 Bi₂O₄ (tetroxide) +5 BiO₃ ⁻ (metabismuthite) Bi₂O₅(pentoxide) B Vanadium (V) +5 VO₂ ⁺ (vanadic) +5 Species/+7, +9 Species(See also POM H₃V₂O₇ ⁻ (pyrovanadate) Complex Anion H₂VO₄ ⁻(orthovanadate) Mediators) VO₃ ⁻ (metavanadate) HVO₄ ⁻² (orthovanadate)VO₄ ⁻³ (orthovanadate) V₂O₅ (pentoxide) H₄V₂O₇ (pyrovanadic acid) HVO₃(metavanadic acid) H₄V₆O₁₇ (hexavanadic acid) +7 VO₄ ⁻ (pervanadate) +9VO₅ ⁻ (hypervanadate) VI B Chromium +3 Cr⁺³ (chromic) +3 Species/+4, +6Species CrOH⁺², Cr(OH)₂ ⁺ (chromyls) +4 Species/+6 Species CrO₂ ⁻, CrO₃⁻³ (chromites) Cr₂O₃ (chromic oxide) Cr(OH)₃ (chromic hydroxide) +4 CrO₂(dioxide) Cr(OH)₄ (hydroxide) +6 H₂CrO₄ (chromic acid) HCrO₄ ⁻ (acidchromate) CrO₄ ⁻² (chromate) Cr₂O₇ ⁻² (dichromate) Molybdenum (Mo) +6HMoO₄ ⁻ (bimolybhate) +6 Species/+7 Species (See also POM MoO₄ ⁻²(molydbate) Complex Anion MoO₃ (molybdic trioxide) Mediators) H₂MoO₄(molybolic acid) +7 MoO₄ ⁻ (permolybdate) Tungsten (W) +6 WO₄ ⁻²tungstic) +6 Species/+8 Species (See also POM WO₃ (trioxide) ComplexAnion H₂WO₄ (tungstic acid) Mediators) +8 WO₅ ⁻² (pertungstic) H₂WO₅(pertungstic acid) VII A Chlorine (Cl) −1 Cl⁻ (chloride) −1 Species/+1,+3, +5, +7 Species +1 HClO (hypochlorous acid) +1 Species/+3, +5, +7Species ClO⁻ (hypochlorite) +3 Species/+5, +7 Species +3 HClO₂ (chlorousacid) +5 Species/+7 Species ClO₂ ⁻ (chlorite) +5 HClO₃ (chloric acid)ClO₃ ⁻ (chlorate) +7 HClO₄ (perchloric acid) ClO₄ ⁻, HClO₅ ⁻², ClO₅ ⁻³,Cl₂O₉ ⁻⁴ (perchlorates) V B Niobium (Nb) +5 NbO₃ ⁻ (metaniobate) +5Species/+7 species (See also POM NbO₄ ⁻³ (orthoniobate) Complex AnionNb₂O₅ (pentoxide) Mediators) HNbO₃ (niobid acid) +7 NbO₄ ⁻ (perniobate)Nb₂O₇ (perniobic oxide) HNbO₄ (perniobic acid) Tantalum (Ta) +5 TaO₃ ⁻(metatantalate) +5 species/+7 species (See also POM TaO₄ ⁻³(orthotanatalate) Complex Anion Ta₂O₅ (pentoxide) Mediators) HTaO₃(tantalic acid) +7 TaO₄ ⁻ (pentantalate) Ta₂O₇ (pertantalate) HTaO₄.H₂O(pertantalic acid) VI A Sulfur (S) +6 H₂SO₄ (sulfuric acid) +6Species/+7, +8 Species HSO₄ ⁻ (bisulfate) SO₄ ⁻² (sulfate) +7 S₂O₈ ⁻²(dipersulfate) +8 H₂SO₅ (momopersulfuric acid) Selenium (Se) +6 H₂Se₂O₄(selenic acid) +6 species/+7 Species HSeO₄ ⁻ (biselenate) SeO₄ ⁻²(selenate) +7 H₂Se₂O₈ (perdiselenic acid) Tellurium (Te) +6 H₂TeO₄(telluric acid) +6 species/+7 species HTeO₄ ⁻ (bitellurate) TeO₄ ⁻²(tellurate) +7 H₂Te₂O₈ (perditellenic acid) Polonium (Po) +2 Po⁺²(polonous) +2, +4 species/+6 Species +4 PoO₃ ⁻² (polonate) +6 PoO₃(peroxide) VII A Bromine (Br) −1 Br⁻ (bromide) −1 Species/+1, +3, +5, +7Species +1 HBrO (hypobromous acid) +1 Species/+3, +5, +7 Species BrO⁻(hypobromitee) +3 Species/+5, +7 Species +3 HBrO₂ (bromous acid) +5Species/+7 Species BrO2⁻ (bromite) +5 HBrO₃ (bromic acid) BrO₃ ⁻(bromate) +7 HBrO₄ (perbromic acid) BrO₄ ⁻, HBrO₅ ⁻², BrO₅ ⁻³, Br₂O₉ ⁻⁴(prebromates) Iodine −1 I⁻ (iodide) −1 Species/+1, +3, +5, +7 Species +1HIO (hypoiodus acid) +1 Species/+3, +5, +7 Species IO⁻ (hypoiodite) +3Species/+5, +7 Species +3 HIO₂ (iodous acid) +5 Species/+7 Species IO₂ ⁻(iodite) +5 HIO₃ (iodic acid) IO₃ ⁻ (iodate) +7 HIO₄ (periodic acid) IO₄⁻, HIO₅ ⁻², IO₅ ⁻³, I₂O₉ ⁻⁴ (periodates) B Manganese (Mn) +2 Mn⁺²(manganeous) +2 Species/+3, +4, +6, +7 Species HMnO₂ ⁻ (dimanganite) +3Species/+4, +6, +7 Species +3 Mn⁺³ (manganic) +4 Species/+6, +7 Species+4 MnO₂ (dioxide) +6 Species/+7 Species +6 MnO₄ ⁻² (manganate) +7 MnO₄ ⁻(permanganate) VIII Period 4 Iron (Fe) +2 Fe⁺² (ferrous) +2 Species/+3,+4, +5, +6 Species HFeO₂ ⁻ (dihypoferrite) +3 Species/+4, +5, +6 Species+3 Fe⁺³, FeOH⁺², Fe(OH)₂ ⁺ (ferric) +4 Species/+5, +6 Species FeO₂ ⁻(ferrite) +5 Species/+6 Species +4 FeO⁺² (ferryl) FeO₂ ⁻² (perferrite)+5 FeO₂ ⁺ (perferryl) +6 FeO₄ ⁻² (ferrate) Cobalt (Co) +2 Co⁺²(cobalous) +2 Species/+3, +4 Species HCoO₂ ⁻ (dicobaltite) +3 Species/+4Species +3 Co⁺³ (cobaltic) Co₂O₃ (cobaltic oxide) +4 CoO₂ (peroxide)H₂CoO₃ (cobaltic acid) Nickel (Ni) +2 Ni⁺² (nickelous) +2 Species/+3,+4, +6 Species NiOH⁺ +3 Species/+4, +6 Species HNiO₂ ⁻ (dinickelite) +4Species/+6 Species NiO₂ ⁻² (nickelite) +3 Ni⁺³ (nickelic) Ni₂O₃(nickelic oxide) +4 NiO₂ (peroxide) +6 NiO₄ ⁻² (nickelate) Period 5Ruthenium (Ru) +2 Ru⁺² +2 Species/+3, +4, +5, +6, +7, +8 Species +3 Ru⁺³+3 Species/+4, +5, +6, +7, +8 Species Ru₂O₃ (sesquioxide) +4 Species/+5,+6, +7, +8 Species Ru(OH)₃ (hydroxide) +5 Spedies/+6, +7, +8 Species +4Ru⁺⁴ (ruthenic) +6 Species/+7, +8 Species RuO₂ (ruthenic dioxide) +7Species/+8 Species Ru(OH)₄ (ruthenic hydroxide) +5 Ru₂O₅ (pentoxide) +6RuO₄ ⁻² (ruthenate) RuO₂ ⁺² (ruthenyl) RuO₃ (trioxide) +7 RuO₄ ⁻(perruthenate) +8 H₂RuO₄ (hyperuthenic acid) HRuO₅ ⁻ (diperruthenate)RuO₄ (ruthenium tetroxide) Rhodium (Rh) +1 Rh⁺ (hyporhodous) +1Species/+2, +3, +4, +6 Species +2 Rh⁺ (rhodous) +2 Species/+3, +4, +6Species +3 Rh⁺³ (rhodic) +3 Species/+4, +6 Species Rh₂O₃ (sesquioxide)+4 Species/+6 Species +4 RhO₂ (rhodic oxide) Rh(OH)₄ (hydroxide) +6 RhO₄⁻² (rhodate) RhO₃ (trioxide) Palladium +2 Pd⁺² (palladous) +2Species/+3, +4, +6 Species PdO₂ ⁻² (palladite) +3 Species/+4, +6 Species+3 Pd₂O₃ (sesquioxide) +4 Species/+6 Species +4 Pd O₃ ⁻² (palladate)PdO₂ (dioxide) Pd(OH)₄ (hydroxide) +6 PdO₃ (peroxide) Period 6 Iridium(Ir) +3 Ir⁺³ (iridic) +3 Species/+4, +6 Species Ir₂O₃ (iridiumsesquioxide) +4 Species/+6 Species Ir (OH)₃ (iridium hydroxide) +4 IrO₂(iridic oxide) Ir (OH)₄ (iridic hydroxide) +6 IrO₄ ⁻² (iridate) IrO₃(iridium peroxide) Platinum (Pt) +2 Pt⁺² (platinous) +2, +3 Species/+4,+6 Species +3 Pt₂O₃ (sesquioxide) +4 Species/+6 Species +4 PtO₃ ⁻²(palatinate) PtO⁺² (platinyl) Pt(OH)⁺³ PtO₂ (platonic oxide) IIIB RareCerium (Ce) +3 Ce⁺³ (cerous) +3 Species/+4, +6 Species earths Ce₂O₃(cerous oxide) +4 Species/+6 Species Ce(OH)₃ (cerous hydroxide) +4 Ce⁺⁴,Ce(OH)⁺³, Ce(OH)₂ ⁺², Ce(OH)₃ ⁺ (ceric) CeO₂ (ceric oxide) +6 CeO₃(peroxide) Praseodymium (Pr) +3 Pr⁺³ (praseodymous) +3 species/+4species Pr₂O₃ (sesquioxide) Pr(OH)₃ (hydroxide) +4 Pr⁺⁴ (praseodymic)PrO₂ (dioxide) Neodymium +3 Nd⁺³ +3 Species/+4 Species Nd₂O₃(sesquioxide) +4 NdO₂ (peroxide) Terbium (Tb) +3 Tb⁺³ +3 Species/+4Species Tb₂O₃ (sesquioxide) +4 TbO₂ (peroxide) Actinides Thorium (Th) +4Th⁺⁴ (thoric) +4 Species/+6 Species ThO⁺² (thoryl) HThO₃ ⁻ (thorate) +6ThO₃ (acid peroxide) Uranium (U) +6 UO₂ ⁺² (uranyl) +6 Species/+8Species UO₃ (uranic oxide) +8 HUO₅ ⁻, UO₅ ⁻² (peruranates) UO₄(peroxide) Neptunium (Np) +5 NpO₂ ⁺ (hyponeptunyl) +5 Species/+6, +8Species Np₂O₅ (pentoxide) +6 Species/+8 Species +6 NpO₂ ⁺² (neptunyl)NpO₃ (trioxide) +8 NpO₄ (peroxide) Plutonium (Pu) +3 Pu⁺³(hypoplutonous) +3 Species/+4, +5, +6 Species +4 Pu⁺⁴ (plutonous) +4Species/+5, +6 Species PuO₂ (dioxide) +5 Species/+6 Species +5 PuO₂ ⁺(hypoplutonyl) Pu₂O₅ (pentoxide) +6 PuO₂ ⁺² (plutonyl) PuO₃ (peroxide)Americium (Am) +3 Am⁺³ (hypoamericious) +4 Am⁺⁴ (americous) AmO₂(dioxide) Am(OH)₄ (hydroxide) +5 AmO₂ ⁺ (hypoamericyl) Am₂O₅ (pentoxide)+6 AmO₂ ⁺² (americyl) AmO₃ (peroxide)

TABLE II ELEMENTS PARTICIPATING AS HETEROATOMS IN HETEROPOLYANIONCOMPLEX ANION REDOX COUPLE MEDIATORS SUB GROUP GROUP ELEMENT I A Lithium(Li), Sodium (Na), Potassium (K), and Cesium (Cs) B Copper (Cu), Silver(Ag), and Gold (Au) II A Beryllium (Be), Magnesium (Mg), Calcium (Ca),Strontium (Sr), and Barium (Ba) B Zinc (Zn), Cadmium (Cd), and Mercury(Hg) III A Boron (B), and Aluminum (Al) B Scandium (Sc), and Yttrium(Y) - (See Rare Earths) IV A Carbon (C), Silicon (Si), Germanium (Ge),Tin (Sn) and Lead (Pb) B Titanium (Ti), Zirconium (Zr), and Hafnium (Hf)V A Nitrogen (N), Phosphorous (P), Arsenic (As), Antimony (Sb), andBismuth (Bi) B Vanadium (V), Niobium (Nb), and Tantalum (Ta) VI A Sulfur(S), Selenium (Se), and Tellurium (Te) B Chromium (Cr), Molybdenum (Mo),and Tungsten (W) VII A Fluorine (F), Chlorine (Cl), Bromine (Br), andIodine (I) B Manganese (Mn), Technetium (Tc), and Rhenium (Re) VIIIPeriod 4 Iron (Fe), Cobalt (Co), and Nickel (Ni) Period 5 Ruthenium(Ru), Rhodium (Rh), and Palladium (Pd) Period 6 Osmium (Os), Iridium(Ir), and Platinum (Pt) IIIB Rare All Earths

1. A treatment of waste process comprises oxidizing mixed waste by (a)dissolution of transuranic elements plutonium, neptunium, americium,curium, and californium, and/or compounds thereof in transuranic waste(TRUW), low level waste (LLW), low level mixed waste (LLMW), specialcase waste (SCW), and greater than class C (GTCC) LLW; (b) destructionof non-fluorocarbon organic component in the waste; or (c)decontamination of transuranic/actinide contaminated equipment, furthercomprising disposing an electrolyte in an electrochemical cell,separating the electrolyte into an anolyte portion and a catholyteportion with an ion-selective membrane, microporous plastic, porousceramic or glass frit or semi permeable membrane, applying a directcurrent voltage between the anolyte portion and the catholyte portion,placing the mixed waste and/or transuranic/actinides materials in theanolyte portion, and oxidizing the mixed waste and/ortransuranic/actinides materials in the anolyte portion with a mediatedelectrochemical oxidation (MEO) process, wherein the anolyte portionfurther comprises a mediator oxidizing species in aqueous solution andcontaining an acid, neutral or alkaline electrolytes, and wherein themediator oxidizing species are simple anion redox couples described inTable I as below: Type I isopolyanions complex anion redox couplesformed by incorporation of Mo, W, V, Nb, Ta, or mixtures thereof asaddenda atoms; Type I heteropolyanions complex anion redox couplesformed by incorporation in to Type I isopolyanions as heteroatoms any ofthe elements listed in Table II either singly or in combination thereof,or heteropolyanions complex anion redox couples containing at least oneheteroatom type element contained in both Table I and Table II below orcombinations of the mediator oxidizing species from any or all of thesegeneric groups: 2-7. (canceled)
 8. The process of claim 1, furthercomprising adding stabilizing compounds to the electrolyte forovercoming and stabilizing the short lifetime of oxidized forms ofhigher oxidation state species of the mediator oxidizing species. 9.(canceled)
 10. The process of claim 1, wherein the mediator oxidizingspecies are super oxidizers which exhibit oxidation potentials of atleast 1.7 volts at 1 molar, 25° C. and pH 1 and which are redox couplespecies that have the capability of producing free radicals of hydroxylor perhydroxyl, and further comprising creating free radical secondaryoxidizers by reacting the super oxidizers with water adding energy froman energy source, ultra sonic and/or ultraviolet, to the anolyte portionand augmenting the secondary oxidation processes, breaking down hydrogenperoxide in the anolyte portion into hydroxyl free radicals andincreasing an oxidizing effect of the secondary oxidation processes, andfurther comprising generating inorganic free radicals in aqueoussolutions from carbonate, azide, nitrite, nitrate, phosphite, phosphate,sulfite, sulfate, selenite, thiocyanate, chloride, bromide, iodide, andformate oxidizing species.
 11. The process of claim 1, furthercomprising using an alkaline solution, aiding decomposing of thebiological materials in mixed waste derived from base promoted esterhydrolysis, saponification, of fatty acids, and forming water solublealkali metal salts of the fatty acids and glycerin in a process similarto the production of soap from animal fat by introducing it into a hotaqueous lye solution.
 12. The process of claim 1, further comprisingusing an alkaline anolyte solution for absorbing CO₂ from the oxidizingof mixed waste materials and forming bicarbonate/carbonate solutions,which subsequently circulate through the electrochemical cell, producingpercarbonate oxidizers. 13-14. (canceled)
 15. The process of claim 1,further comprising impressing an AC voltage upon the direct currentvoltage for retarding formation of cell performance limiting surfacefilms on the electrodes or the membrane. 16-19. (canceled)
 20. Theprocess of claim 1, further comprising introducing an ultrasonic energyinto the anolyte portion, rupturing cell membranes in the biologicalmaterials in mixed waste by momentarily raising local temperature andpressure within the cell membranes with the ultrasonic energy to aboveseveral thousand degrees and thousand atmospheres, and causing cellmembrane failure, and wherein the added energy comprises usingultrasonic energy and inducing microscopic bubble expansion andimplosion for reducing in size individual second phase mixed wastevolumes dispersed in the anolyte.
 21. The process of claim 1, furthercomprising introducing ultraviolet energy into the anolyte portion anddecomposing hydrogen peroxide into hydroxyl free radicals therein,thereby increasing efficiency of the process by converting product ofelectron consuming parasitic reactions, hydrogen peroxide, into viablefree radical secondary oxidizers without consumption of additionalelectrons.
 22. The process of claim 1, further comprising adding asurfactant to the anolyte portion for promoting dispersion of the mixedwaste or intermediate stage reaction products within the aqueoussolution when the mixed waste or reaction products are not water-solubleand tend to form immiscible layers.
 23. The process of claim 1, furthercomprising attacking specific organic molecules in the mixed waste withthe mediator oxidizing species while operating at a sufficiently lowtemperatures and preventing formation of dioxins and furans.
 24. Theprocess of claim 1, further comprising breaking down the mixed wastematerials into biological and organic compounds and attacking thesecompounds using as the mediator simple and/or complex anion redox couplemediators or inorganic free radicals and generating organic freeradicals.
 25. The process of claim 1, further comprising raising normalvalence state mediator anions to a higher valence state by stripping themediator anions of electrons in the electrochemical cell, whereinoxidized forms of weaker redox couples present in the mediator oxidizingspecies are produced by similar anodic oxidation or reaction withoxidized forms of stronger redox couples present and the oxidizedspecies of the redox couples oxidize molecules of the mixed waste andare themselves converted to their reduced form, whereupon they areoxidized by the aforementioned mechanisms and the redox cycle continues.26-30. (canceled)
 31. The process of claim 1, further comprising usingthe mediator oxidizing species that are found in situ in the mixed wasteto be decomposed, by circulating the mixed waste-anolyte mixture throughthe electrochemical cell wherein an oxidized form of an in situreversible redox couple is formed by anodic oxidizing or reacting withan oxidized form of a more powerful redox couple added to or alreadypresent in the anolyte portion and anodically oxidized in theelectrochemical cell, thereby destroying biological and organicmaterials in the mixed waste.
 32. The process of claim 1, furthercomprising using an alkaline electrolyte selected from a groupconsisting of NaOH or KOH and combinations thereof, with the mediatoroxidizing species, wherein a reduced form of a mediator redox couple hassufficient solubility in said electrolyte for allowing desired oxidationof biological and organic materials in the mixed waste.
 33. The processof claim 1, wherein the oxidation potential of redox reactions of themediator oxidizing species and the biological and organic molecules inthe mixed waste producing hydrogen ions are inversely proportional toelectrolyte pH, and thus with a selection of a mediator redox coupleincreasing the electrolyte pH reduces the electric potential required,thereby reducing electric power consumed per unit mass of the mixedwaste destroyed.
 34. The process of claim 1, wherein the electrolyte isan aqueous solution chosen from acids, alkalines and salt electrolytes.35. (canceled)
 36. The process of claim 1, further comprisinginterchanging the mediator oxidizing species without changing equipment,and wherein the anolyte and catholyte portions of electrolyte areindependent of one another and comprise aqueous solutions of acids,alkali or salts. 37-43. (canceled)
 44. The process of claim 1, whereinthe oxidizing and destroying mixed waste materials comprises oxidizingand destroying a combination of liquids and solids in mixed waste. 45.The process of claim 1, further comprising requiring removing andtreating precipitates resulting from combinations of the oxidizingspecies and other species released from the mixed waste duringdestruction and sterilization.
 46. (canceled)
 47. The process of claim1, further comprising separating a catholyte portion of the electrolytefrom the anolyte portion with a membrane, operating the electrochemicalcell at a higher current density across the membrane, and near a limitover which there is the possibility that metallic anions may leakthrough the membrane in small quantities, and recovering the metallicanions through a resin column, thus allowing a greater rate ofdestruction of mixed waste materials in the anolyte portion.
 48. Theprocess of claim 1, wherein the catholyte portion further comprises anaqueous solution and the electrolyte in the solution is composed ofacids, alkali or neutral, and further comprising adding oxygen to thesolution when HNO₃ or NO₃ ⁻ can occur in the catholyte portion,controlling concentration of electrolyte in the catholyte to maintainconductivity of the catholyte portion desired in the electrochemicalcell, providing mechanical mixing and/or ultrasonic energy inducedmicroscopic bubble formation, and implosion for vigorous mixing in thecatholyte solution for oxidizing the nitrous acid and small amounts ofnitrogen oxides NO_(x), introducing air into the catholyte portion forpromoting the oxidizing of the nitrous acid and the small amounts ofNO_(x), and diluting any hydrogen produced in the catholyte portionbefore releasing the air and hydrogen.
 49. Apparatus for the use of atreatment of waste process comprises oxidizing mixed waste by (a)dissolution of transuranic elements plutonium, neptunium, americium,curium, and californium, and/or compounds thereof in transuranic waste(TRUW), low level waste (LLW), low level mixed waste (LLMW), specialcase waste (SCW), and greater than class C (GTCC) LLW;. (b) destructionof non-fluorocarbon organic component in the waste; or (c)decontamination of transuranic/actinide contaminated equipment, furthercomprising an electrochemical cell, an aqueous electrolyte disposed inthe electrochemical cell, a hydrogen or hydronium ion-permeable orselective membrane, disposed in the electrochemical cell for separatingthe cell into anolyte and catholyte chambers and separating theelectrolyte into aqueous anolyte and catholyte portions, electrodesfurther comprising an anode and a cathode disposed in theelectrochemical cell respectively in the anolyte and catholyte chambersand in the anolyte and catholyte portions of the electrolyte, a powersupply connected to the anode and the cathode for applying a directcurrent voltage between the anolyte and the catholyte portions of theelectrolyte, and oxidizing of the materials in the anolyte portion witha mediated electrochemical oxidation (MEO) process wherein the anolyteportion further comprises a mediator in aqueous solution for producingreversible redox couples used as oxidizing species and the electrolyteis an acid, neutral or alkaline aqueous solution.
 50. The apparatus ofclaim 49, further comprising an anolyte reaction chamber and buffer tankhousing the bulk of the anolyte solution, an input pump to enter liquidmixed waste materials into the anolyte reaction chamber, a spray headand stream head to introduce the anolyte from the electrochemical cellinto the anolyte reaction chamber in such a manner as to promote mixingof the incoming anolyte and the anolyte mixture in the anolyte reactionchamber, a hinged lid to allow insertion of mixed waste into the anolyteportion as liquid, solid of combination of both, a locking latch tosecure the lid during operation of the system, a suction pump attachedto the buffer tank to pump anolyte from the buffer tank to the anolytereaction chamber, a input pump to pump anolyte from the anolyte reactionchamber back to the buffer tank, and an air pump to pump off gases fromthe anolyte reaction chamber back to the buffer tank for furtheroxidation.
 51. (canceled)
 52. The process of claim 1, further comprisingadditives disposed in the electrolyte for contributing to kinetics ofthe mediated electrochemical processes while keeping it from becomingdirectly involved in the oxidizing of the mixed waste materials, andstabilizer compounds disposed in the electrolyte for stabilizing higheroxidation state species of oxidized forms of the reversible redoxcouples used as the mediator oxidizing species in the electrolyte.53-63. (canceled)
 64. The apparatus of claim 49, wherein the powersupply energizes the electrochemical cell at a potential levelsufficient to form the oxidized form of the redox couple having thehighest oxidation potential in the anolyte, and further comprising aheat exchanger connected to the anolyte chamber for controllingtemperature between 0° C. and slightly below the boiling temperature ofthe anolyte with the heat exchanger before the anolyte enters theelectrochemical cell enhancing the generation of oxidized forms of theanion redox couple mediator, and adjusting the temperature of theanolyte to the range between 0° C. and slightly below the boilingtemperature when entering the anolyte reaction chamber. 65-71.(canceled)
 72. The apparatus of claim 49, further comprising anultrasonic source connected to the anolyte for augmenting secondaryoxidation processes by heating hydrogen peroxide containing electrolyteto 4800° C., at 1000 atmospheres for dissociating hydrogen peroxide intohydroxyl free radicals and thus increasing concentration of oxidizingspecies and rate of waste destruction and for irradiating cell membranesin biological materials in the mixed waste to momentarily raise thetemperature within the cell membranes to above several thousand degrees,causing failure of the cell membranes, and creating greater exposure ofcell contents to oxidizing species in the anolyte.
 73. (canceled) 74.The apparatus of claim 49, further comprising an anolyte reactionchamber holding most of the anolyte portion and a foraminous basket, apenetrator attached to the basket to puncture solids increasing theexposed area, and further comprising an external CO₂ vent connected tothe reaction chamber for releasing CO₂ into the atmosphere, a hinged lidattached to the reaction chamber allowing insertion of waste into theanolyte portion as liquid, solid, or mixtures of liquids and solids, ananolyte pump connected to the reaction chamber, an inorganic compoundsremoval and treatment system connected to the anolyte pump for removingchlorides, and other precipitate forming anions present in biologicaland organic waste being processed, thereby precluding formation ofunstable oxycompounds.
 75. The apparatus of claim 49, further comprisingan off-gas cleaning system, comprising scrubber/absorption columnsconnected to the vent, a condenser connected to the anolyte reactionchamber, whereby non-condensable incomplete oxidation products, lowmolecular weight organics and carbon monoxide are reduced to acceptablelevels for atmospheric release by the gas cleaning system, and whereinthe anolyte off-gas is contacted in the gas cleaning system wherein thenoncondensibles from the condenser are introduced into the lower portionof the gas cleaning system through a flow distribution system and asmall side stream of freshly oxidized anolyte direct from theelectrochemical cell is introduced into the upper portion of the column,resulting in a gas phase continuously reacting with the oxidizingmediator species as it rises up the column past the down flowinganolyte, and external drain, for draining to an organic compound removalsystem and the inorganic compounds removal and treatment system, and fordraining the anolyte system, wherein the organic compounds recoverysystem is used to recover mixed waste materials that are benign and donot need further treatment, and mixed waste materials that will be usedin the form they have been reduced.
 76. The apparatus of claim 49,further comprising thermal control units connected to heat or cool theanolyte to a selected temperature range when anolyte is circulated intothe reaction chamber through the electrochemical cell by pump on theanode chamber side of the membrane, a flush for flushing the anolyte, anin-line filter preventing solid particles large enough to clogelectrochemical cell flow paths from exiting the reaction chamber aninorganic compound removal and treatment system and drain outletsconnected to the anolyte reaction chamber, whereby residue is pacifiedin the form of a salt and periodically removed, and a filter is locatedat the base of the reaction chamber to limit the size of exiting solidparticles to approximately 1 mm in diameter.
 77. (canceled)
 78. Theapparatus of claim 49, further comprising an electrolyte containmentboundary composed of materials resistant to the oxidizing electrolyteselected from a group consisting of stainless steel, PTFE, PTFE linedtubing, glass and ceramics, and combinations thereof.
 79. The apparatusof claim 49, further comprising an anolyte recovery system connected toa catholyte pump, a catholyte reservoir connected to the cathode portionof the electrochemical cell, a thermal control unit connected to thecatholyte reservoir for varying the temperature of the catholyteportion, a bulk of the catholyte portion being resident in a catholytereservoir, wherein the catholyte portion of the electrolyte flows into acatholyte reservoir, and further comprising an air sparge connected tothe catholyte reservoir for introducing air into the catholytereservoir.
 80. The apparatus of claim 49, further comprising an anolyterecovery system wherein some anions in the anolyte cross the membraneand are removed through the anolyte recovery system to maintain processefficiency or cell operability and for reintroducing the recoveredmediator anions into the anolyte chamber upon collection from thecatholyte electrolyte, an off-gas cleaning system connected to thecatholyte reservoir for cleaning gases before release into theatmosphere, and an atmospheric vent connected to the off-gas cleaningsystem for releasing gases into the atmosphere, wherein cleaned gas fromthe off-gas cleaning system is combined with unreacted components of theair introduced into the system and discharged through the atmosphericvent
 47. 81. The apparatus of claim 49, further comprising a screwed topon the catholyte reservoir to facilitate flushing out the catholytereservoir, a mixer connected to the catholyte reservoir for stirring thecatholyte, a catholyte pump connected to the catholyte reservoir forcirculating catholyte back to the electrochemical cell, a drain fordraining catholyte, a flush for flushing the catholyte system, and anair sparge connected to the housing for introducing air into thecatholyte reservoir, wherein the catholyte portion of the electrolyte iscirculated by pump through the electrochemical cell on the cathode sideof the membrane, and wherein contact of oxidizing gas with the catholyteportion of the electrolyte is enhanced by promoting gas/liquid contactby mechanical and/or ultrasonic mixing.
 82. (canceled)
 83. The apparatusof claim 49, further comprising a controller, a microprocessor, amonitor and a keyboard connected to the cell for inputting commands tothe controller through the keyboard responding to the informationdisplayed on the monitor, a controller with a control keyboard for inputof commands and data, a monitor screen to display operations andfunctions of the systems status lights for displaying information aboutstatus of the treatment of the mixed waste material, a program in thecontroller sequencing the steps for operation of the apparatus, programhaving pre-programmed sequences of operations the operator follows orchooses other sequences of operations, the controller allows theoperator to select sequences within limits that assure a safe andreliable operation, the controller sends digital commands that regulateelectrical power to pumps, mixers, thermal controls, ultravioletsources, ultrasonic sources, CO₂ vents, air sparge, and theelectrochemical cell, the controller receives component response andstatus from the components, the controller sends digital commands to thesensors to access sensor information through sensor responses, sensorsin the apparatus provide digital information on the state of components,sensors measure flow rate, temperature, pH, CO₂ venting, degree ofoxidation, and air sparging, the controller receives status informationon electrical potential across the electrochemical cell or individualcells in a multi-cell configuration and between reference electrodesinternal to the anolyte and catholyte chambers of the electrochemicalcells and the current flowing between the electrodes within each cell.84-85. (canceled)
 86. The apparatus of claim 49, further comprising amixed waste oxidizing process with an operator engaging an ‘ON’ buttonon a control keyboard, a system controller which further comprises amicroprocessor, running a program and controlling a sequence ofoperations, a monitor screen displaying process steps in propersequence, status lights on a panel providing status of the process,opening a lid and placing the mixed waste in a basket as a liquid,solid, or a mixture of liquids and solids, retaining a solid portion ofthe mixed waste and flowing a liquid portion through the basket and intoan anolyte reaction chamber, activating a locking latch after the mixedwaste is placed in the basket, activating pumps and circulating anolyteand catholyte, once the circulating is established throughout thesystem, operating mixers, once flow is established, turning on thermalcontrol units, and initiating anodic oxidizing and electrolyte heatingprograms, energizing an electrochemical cell to electric potential andcurrent density determined by the program of the controller, usingprogrammed electrical power and electrolyte temperature ramps formaintaining a predetermined mixed waste destruction rate profile as arelatively constant reaction rate as more reactive waste components areoxidized, thus resulting in the remaining waste becoming less and lessreactive, providing more vigorous oxidizing conditions by activatingultrasonic and ultraviolet systems in the anolyte reaction chamber andcatholyte reservoir, releasing CO₂ from the biological and organicmaterials in the mixed waste oxidizing process in the anolyte reactionchamber, activating air sparge and atmospheric vent in a catholytesystem, monitoring progress of the process in the controller by cellvoltages and currents, monitoring CO₂, CO, and O₂ gas composition forCO₂, CO and oxygen content, decomposing the mixed waste into water andCO₂, the latter being discharged out of the CO₂ vent, air spargingdrawing air into a catholyte reservoir, and discharging excess air outof an atmospheric vent, determining with an oxidation sensor thatdesired degree of mixed waste destruction has been obtained, setting thesystem to standby, and executing system shutdown using the controllerkeyboard system operator.
 87. The process of claim 49, furthercomprising placing the system in a standby mode during the day andadding mixed waste as it is generated throughout the day, placing thesystem in full activation during non-business hours, operating thesystem at low temperature and ambient atmospheric pressure and notgenerating toxic compounds during the oxidation of the mixed waste,making the process indoors compatible, scaling the system between unitssmall enough for use by a single practitioner and units large enough forreplacing hospital incinerators, releasing CO₂ oxidation product fromthe anolyte system out through the CO₂ vent, and venting off-gasproducts from the catholyte reservoir through the atmospheric vent. 88.(canceled)